esp_modem: Moved to component folder

components/esp_modem/include/cxx_include/esp_modem_api.hpp

@@ -0,0 +1,107 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_API_HPP_
+#define _ESP_MODEM_API_HPP_
+
+#include <memory>
+#include "cxx_include/esp_modem_dce.hpp"
+#include "cxx_include/esp_modem_dce_module.hpp"
+
+struct esp_modem_dte_config;
+struct esp_modem_dce_config;
+
+
+namespace esp_modem {
+
+class DTE;
+typedef struct esp_netif_obj esp_netif_t;
+
+
+/**
+ * @defgroup ESP_MODEM_INIT_DTE ESP_MODEM Initialization API for DTE
+ * @brief Create DTE's
+ */
+/** @addtogroup ESP_MODEM_INIT_DTE
+* @{
+*/
+
+using dce_config = ::esp_modem_dce_config;
+using dte_config = ::esp_modem_dte_config;
+
+/**
+ * @brief Create UART DTE
+ * @param config DTE configuration
+ * @return shared ptr to DTE on success
+ *         nullptr on failure (either due to insufficient memory or wrong dte configuration)
+ *         if exceptions are disabled the API abort()'s on error
+ */
+std::shared_ptr<DTE> create_uart_dte(const dte_config *config);
+
+/**
+ * @brief Create VFS DTE
+ * @param config DTE configuration
+ * @return shared ptr to DTE on success
+ *         nullptr on failure (either due to insufficient memory or wrong dte configuration)
+ *         if exceptions are disabled the API abort()'s on error
+ */
+std::shared_ptr<DTE> create_vfs_dte(const dte_config *config);
+
+
+/**
+ * @}
+ */
+
+/**
+ * @defgroup ESP_MODEM_INIT_DCE ESP_MODEM Initialization API for DCE
+ * @brief ESP_MODEM Initialization API for DCE
+ */
+/** @addtogroup ESP_MODEM_INIT_DCE
+* @{
+*/
+
+/**
+ * @brief Create DCE based on SIM7600 module
+ * @param config DCE configuration
+ * @param DTE reference to the communicating DTE
+ * @param netif reference to the network interface
+ *
+ * @return unique ptr to the created DCE on success
+ *         nullptr on failure
+ *         if exceptions are disabled the API abort()'s on error
+ */
+std::unique_ptr<DCE> create_SIM7600_dce(const dce_config *config, std::shared_ptr<DTE> dte, esp_netif_t *netif);
+
+/**
+ * @brief Create DCE based on SIM800 module
+ */
+std::unique_ptr<DCE> create_SIM800_dce(const dce_config *config, std::shared_ptr<DTE> dte, esp_netif_t *netif);
+
+/**
+ * @brief Create DCE based on BG96 module
+ */
+std::unique_ptr<DCE> create_BG96_dce(const dce_config *config, std::shared_ptr<DTE> dte, esp_netif_t *netif);
+
+/**
+ * @brief Create generic DCE
+ */
+std::unique_ptr<DCE> create_generic_dce(const dce_config *config, std::shared_ptr<DTE> dte, esp_netif_t *netif);
+
+/**
+ * @}
+ */
+
+} // namespace esp_modem
+
+#endif // _ESP_MODEM_API_HPP_

components/esp_modem/include/cxx_include/esp_modem_cmux.hpp

@@ -0,0 +1,112 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_CMUX_HPP_
+#define _ESP_MODEM_CMUX_HPP_
+
+#include "esp_modem_terminal.hpp"
+
+namespace esp_modem {
+
+constexpr size_t max_terms = 2;
+/**
+ * @defgroup ESP_MODEM_CMUX ESP_MODEM CMUX class
+ * @brief Definition of CMUX terminal
+ */
+/** @addtogroup ESP_MODEM_CMUX
+* @{
+*/
+
+/**
+ * @brief CMUX state machine
+ */
+enum class cmux_state {
+    INIT,
+    HEADER,
+    PAYLOAD,
+    FOOTER,
+    RECOVER,
+};
+
+/**
+ * @brief CMUX terminal abstraction
+ *
+ * This class inherits from Terminal class, as it is a Terminal, but is also composed of another Terminal,
+ * which is used to communicate with the modem, i.e. the original Terminal which has been multiplexed.
+ *
+ * @note Implementation of CMUX protocol is experimental
+ */
+class CMuxInstance;
+
+/**
+ * @brief CMux class which consumes the original terminal and creates multiple virtual terminals from it.
+ * This class is not usable applicable as a DTE terminal
+ */
+class CMux {
+public:
+    explicit CMux(std::unique_ptr<Terminal> t, std::unique_ptr<uint8_t[]> b, size_t buff_size):
+            term(std::move(t)), buffer_size(buff_size), buffer(std::move(b)), payload_start(nullptr), total_payload_size(0) {}
+    ~CMux() = default;
+    [[nodiscard]] bool init();
+    void set_read_cb(int inst, std::function<bool(uint8_t *data, size_t len)> f);
+
+    int write(int i, uint8_t *data, size_t len);
+private:
+    std::function<bool(uint8_t *data, size_t len)> read_cb[max_terms];
+    void data_available(uint8_t *data, size_t len);
+    void send_sabm(size_t i);
+    std::unique_ptr<Terminal> term;
+    cmux_state state;
+    uint8_t dlci;
+    uint8_t type;
+    size_t payload_len;
+    uint8_t frame_header[6];
+    size_t frame_header_offset;
+    size_t buffer_size;
+    std::unique_ptr<uint8_t[]> buffer;
+    bool on_cmux(uint8_t *data, size_t len);
+    static uint8_t fcs_crc(const uint8_t frame[6]);
+    Lock lock;
+    int instance;
+    int sabm_ack;
+    uint8_t *payload_start;
+    size_t total_payload_size;
+
+};
+
+/**
+ * @brief This represents a specific instance of a CMUX virtual terminal. This class also implements Terminal interface
+ * and as such could be used as a DTE's terminal.
+ */
+class CMuxInstance: public Terminal {
+public:
+    explicit CMuxInstance(std::shared_ptr<CMux> parent, int i): cmux(std::move(parent)), instance(i) {}
+
+    int write(uint8_t *data, size_t len) override { return cmux->write(instance, data, len); }
+    void set_read_cb(std::function<bool(uint8_t *data, size_t len)> f) override { return cmux->set_read_cb(instance, std::move(f)); }
+    int read(uint8_t *data, size_t len) override { return  0; }
+    void start() override { }
+    void stop() override { }
+private:
+    std::shared_ptr<CMux> cmux;
+    int instance;
+};
+
+/**
+ * @}
+ */
+
+} // namespace esp_modem
+
+#endif // _ESP_MODEM_CMUX_HPP_

components/esp_modem/include/cxx_include/esp_modem_command_library.hpp

@@ -0,0 +1,59 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_COMMAND_LIBRARY_HPP_
+#define _ESP_MODEM_COMMAND_LIBRARY_HPP_
+
+#include "esp_modem_dte.hpp"
+#include "esp_modem_dce_module.hpp"
+#include "esp_modem_types.hpp"
+#include "generate/esp_modem_command_declare.inc"
+
+namespace esp_modem {
+namespace dce_commands {
+
+/**
+ * @defgroup ESP_MODEM_DCE_COMMAND ESP_MODEM DCE command library
+ * @brief Library of the most useful DCE commands
+ */
+/** @addtogroup ESP_MODEM_DCE_COMMAND
+ * @{
+ */
+
+/**
+ * @brief Declaration of all commands is generated from esp_modem_command_declare.inc
+ */
+#define ESP_MODEM_DECLARE_DCE_COMMAND(name, return_type, num, ...) \
+        return_type name(CommandableIf *t, ## __VA_ARGS__);
+
+        DECLARE_ALL_COMMAND_APIS(declare name(Commandable *p, ...);)
+
+#undef ESP_MODEM_DECLARE_DCE_COMMAND
+
+/**
+ * @brief Following commands that are different for some specific modules
+ */
+command_result get_battery_status_sim7xxx(CommandableIf* t, int& voltage, int &bcs, int &bcl);
+command_result power_down_sim7xxx(CommandableIf* t);
+command_result power_down_sim8xx(CommandableIf* t);
+command_result set_data_mode_sim8xx(CommandableIf* t);
+
+/**
+ * @}
+ */
+
+} // dce_commands
+} // esp_modem
+
+#endif //_ESP_MODEM_COMMAND_LIBRARY_HPP_

components/esp_modem/include/cxx_include/esp_modem_dce.hpp

@@ -0,0 +1,114 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_DCE_HPP_
+#define _ESP_MODEM_DCE_HPP_
+
+#include <utility>
+#include "cxx_include/esp_modem_netif.hpp"
+#include "cxx_include/esp_modem_dce_module.hpp"
+
+namespace esp_modem {
+
+/**
+ * @defgroup ESP_MODEM_DCE
+ * @brief Definition of DCE abstraction
+ */
+/** @addtogroup ESP_MODEM_DCE
+ * @{
+ */
+
+
+/**
+ * @brief Helper class responsible for switching modes of the DCE's
+ */
+class DCE_Mode {
+public:
+    DCE_Mode(): mode(modem_mode::COMMAND_MODE) {}
+    ~DCE_Mode() = default;
+    bool set(DTE *dte, ModuleIf *module, Netif &netif, modem_mode m);
+    modem_mode get();
+
+private:
+    modem_mode mode;
+
+};
+
+/**
+ * @brief General DCE class templated on a specific module. It is responsible for all the necessary transactions
+ * related to switching modes and consequent synergy with aggregated objects of DTE, Netif and a specific Module
+ */
+template<class SpecificModule>
+class DCE_T {
+    static_assert(std::is_base_of<ModuleIf, SpecificModule>::value, "DCE must be instantiated with Module class only");
+public:
+    explicit DCE_T(const std::shared_ptr<DTE>& dte, std::shared_ptr<SpecificModule> dev, esp_netif_t * netif):
+            dte(dte), device(std::move(dev)), netif(dte, netif)
+    { }
+
+    ~DCE_T() = default;
+
+    /**
+     * @brief Set data mode!
+     */
+    void set_data() { set_mode(modem_mode::DATA_MODE); }
+
+    void exit_data() { set_mode(modem_mode::COMMAND_MODE); }
+
+    void set_cmux() { set_mode(modem_mode::CMUX_MODE); }
+
+    SpecificModule* get_module() { return device.get(); }
+
+    command_result command(const std::string& command, got_line_cb got_line, uint32_t time_ms)
+    {
+        return dte->command(command, std::move(got_line), time_ms);
+    }
+
+    bool set_mode(modem_mode m) { return mode.set(dte.get(), device.get(), netif, m); }
+
+protected:
+    std::shared_ptr<DTE> dte;
+    std::shared_ptr<SpecificModule> device;
+    Netif netif;
+    DCE_Mode mode;
+};
+
+/**
+ * @brief Common abstraction of the modem DCE, specialized by the GenericModule which is a parent class for the supported
+ * defices and most common modems, as well.
+ */
+class DCE: public DCE_T<GenericModule> {
+public:
+
+    using DCE_T<GenericModule>::DCE_T;
+#define ESP_MODEM_DECLARE_DCE_COMMAND(name, return_type, num, ...) \
+    template <typename ...Agrs> \
+    return_type name(Agrs&&... args)   \
+    {   \
+        return device->name(std::forward<Agrs>(args)...); \
+    }
+
+    DECLARE_ALL_COMMAND_APIS(forwards name(...) { device->name(...); } )
+
+#undef ESP_MODEM_DECLARE_DCE_COMMAND
+
+};
+
+/**
+ * @}
+ */
+
+} // esp_modem
+
+#endif // _ESP_MODEM_DCE_HPP_

components/esp_modem/include/cxx_include/esp_modem_dce_factory.hpp

@@ -0,0 +1,249 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_DCE_FACTORY_HPP_
+#define _ESP_MODEM_DCE_FACTORY_HPP_
+
+/**
+ * @defgroup ESP_MODEM_DCE_FACTORY
+ * @brief DCE modem factory
+ */
+
+
+namespace esp_modem::dce_factory {
+
+using config = ::esp_modem_dce_config;
+
+/** @addtogroup ESP_MODEM_DCE_FACTORY
+* @{
+*/
+
+
+/**
+ * @brief Helper class for creating a uder define pointer in a specific way, either as a plain pointer, shared_ptr or unique_ptr
+ */
+class FactoryHelper {
+public:
+    static std::unique_ptr<PdpContext> create_pdp_context(std::string &apn);
+
+    template <typename T, typename Ptr, typename ...Args>
+    static auto make(Args&&... args) -> typename std::enable_if<std::is_same<Ptr, T*>::value, T*>::type
+    {
+        return new T(std::forward<Args>(args)...);
+    }
+
+    template <typename T, typename Ptr, typename ...Args>
+    static auto make(Args&&... args) ->  typename std::enable_if<std::is_same<Ptr, std::shared_ptr<T>>::value, std::shared_ptr<T>>::type
+    {
+        return std::make_shared<T>(std::forward<Args>(args)...);
+    }
+
+    template <typename T, typename Ptr = std::unique_ptr<T>, typename ...Args>
+    static auto make(Args&&... args) -> typename std::enable_if<std::is_same<Ptr, std::unique_ptr<T>>::value, std::unique_ptr<T>>::type
+    {
+        return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
+    }
+
+};
+
+/**
+ * @brief Builder class for building a DCE_T<Module> in a specific way, either form a Module object or by default from the DTE and netif
+ */
+template<typename Module>
+class Builder {
+    static_assert(std::is_base_of<ModuleIf, Module>::value, "Builder must be used only for Module classes");
+public:
+    Builder(std::shared_ptr<DTE> x, esp_netif_t* esp_netif): dte(std::move(x)), device(nullptr), netif(esp_netif)
+    {
+        throw_if_false(netif != nullptr, "Null netif");
+    }
+
+    Builder(std::shared_ptr<DTE> dte, esp_netif_t* esp_netif, std::shared_ptr<Module> dev): dte(std::move(dte)), device(std::move(dev)), netif(esp_netif)
+    {
+        throw_if_false(netif != nullptr, "Null netif");
+    }
+
+    ~Builder()
+    {
+        throw_if_false(device == nullptr, "module was captured or created but never used");
+    }
+
+    template<typename Ptr>
+    auto create_module(const esp_modem_dce_config *config) -> Ptr
+    {
+        return FactoryHelper::make<Module, Ptr>(dte, config);
+    }
+
+    template<typename DceT, typename Ptr>
+    auto create(const esp_modem_dce_config *config) -> Ptr
+    {
+        if (dte == nullptr)
+            return nullptr;
+        if (device == nullptr) {
+            device = create_module<decltype(device)>(config);
+            if (device == nullptr)
+                return nullptr;
+        }
+        return FactoryHelper::make<DceT, Ptr>(std::move(dte), std::move(device), netif);
+    }
+
+private:
+    std::shared_ptr<DTE> dte;
+    std::shared_ptr<Module> device;
+    esp_netif_t *netif;
+};
+
+/**
+ * @brief Specific modem choice when creating by the Factory
+ */
+enum class Modem {
+    GenericModule,      /*!< Default generic module with the most common commands */
+    SIM7600,            /*!< Derived from the GenericModule, specifics applied to SIM7600 model */
+    BG96,               /*!< Derived from the GenericModule, specifics applied to BG69 model */
+    SIM800,             /*!< Derived from the GenericModule with specifics applied to SIM800 model */
+};
+
+/**
+ * @brief Factory class for creating virtual DCE objects based on the configuration of the supplied module.
+ * This could also be used to create a custom module or a DCE_T<module>, provided user app derives from this factory.
+ */
+class Factory {
+public:
+    explicit Factory(Modem modem): m(modem) {}
+
+    /**
+     * @brief Create a default unique_ptr DCE in a specific way (from the module)
+     * @tparam Module Specific Module used in this DCE
+     * @tparam Args Arguments to the builder, i.e. constructor of esp_modem::DCE_T class
+     * @param cfg DCE configuration structure ::esp_modem_dte_config
+     * @param args typically a DTE object and a netif handle for PPP network
+     * @return unique_ptr DCE of the created DCE on success
+     */
+    template <typename Module, typename ...Args>
+    static std::unique_ptr<DCE> build_unique(const config *cfg, Args&&... args)
+    {
+        return build_generic_DCE<Module, DCE, std::unique_ptr<DCE>>(cfg, std::forward<Args>(args)...);
+    }
+
+    /**
+     * @brief Create a DCE
+     * @tparam Module Specific Module used in this DCE
+     * @tparam Args Arguments to the builder, i.e. constructor of esp_modem::DCE_T class
+     * @param cfg DCE configuration structure ::esp_modem_dte_config
+     * @param args typically a DTE object and a netif handle for PPP network
+     * @return DCE pointer the created DCE on success
+     */
+    template <typename Module, typename ...Args>
+    static DCE* build(const config *cfg, Args&&... args)
+    {
+        return build_generic_DCE<Module, DCE>(cfg, std::forward<Args>(args)...);
+    }
+
+
+    template <typename Module, typename ...Args>
+    static std::shared_ptr<Module> build_shared_module(const config *cfg, Args&&... args)
+    {
+        return build_module_T<Module>(cfg, std::forward<Args>(args)...);
+    }
+
+
+    template <typename ...Args>
+    std::shared_ptr<GenericModule> build_shared_module(const config *cfg, Args&&... args)
+    {
+        switch (m) {
+            case Modem::SIM800:
+                return build_shared_module<SIM800>(cfg, std::forward<Args>(args)...);
+            case Modem::SIM7600:
+                return build_shared_module<SIM7600>(cfg, std::forward<Args>(args)...);
+            case Modem::BG96:
+                return build_shared_module<BG96>(cfg, std::forward<Args>(args)...);
+            case Modem::GenericModule:
+                return build_shared_module<GenericModule>(cfg, std::forward<Args>(args)...);
+            default:
+                break;
+        }
+        return nullptr;
+    }
+
+    /**
+     * @brief Create a default unique_ptr DCE generically, with the chosen module derived from the GenericModule
+     * @tparam Args Arguments to the builder, i.e. constructor of esp_modem::DCE_T class
+     * @param cfg DCE configuration structure ::esp_modem_dte_config
+     * @param args typically a DTE object and a netif handle for PPP network
+     * @return unique_ptr DCE of the created DCE on success
+     */
+    template <typename ...Args>
+    std::unique_ptr<DCE> build_unique(const config *cfg, Args&&... args)
+    {
+        switch (m) {
+            case Modem::SIM800:
+                return build_unique<SIM800>(cfg, std::forward<Args>(args)...);
+            case Modem::SIM7600:
+                return build_unique<SIM7600>(cfg, std::forward<Args>(args)...);
+            case Modem::BG96:
+                return build_unique<BG96>(cfg, std::forward<Args>(args)...);
+            case Modem::GenericModule:
+                return build_unique<GenericModule>(cfg, std::forward<Args>(args)...);
+            default:
+                break;
+        }
+        return nullptr;
+    }
+
+    template <typename ...Args>
+    DCE* build(const config *cfg, Args&&... args)
+    {
+        switch (m) {
+            case Modem::SIM800:
+                return build<SIM800>(cfg, std::forward<Args>(args)...);
+            case Modem::SIM7600:
+                return build<SIM7600>(cfg, std::forward<Args>(args)...);
+            case Modem::BG96:
+                return build<BG96>(cfg, std::forward<Args>(args)...);
+            case Modem::GenericModule:
+                return build<GenericModule>(cfg, std::forward<Args>(args)...);
+            default:
+                break;
+        }
+        return nullptr;
+    }
+
+private:
+    Modem m;
+
+protected:
+    template <typename Module, typename Ptr = std::shared_ptr<Module>, typename ...Args>
+    static Ptr build_module_T(const config *cfg, Args&&... args)
+    {
+        Builder<Module> b(std::forward<Args>(args)...);
+        return b.template create_module<Ptr>(cfg);
+    }
+
+
+    template <typename Module, typename Dce = DCE_T<Module>, typename DcePtr = Dce*,  typename ...Args>
+    static DcePtr build_generic_DCE(const config *cfg, Args&&... args)
+    {
+        Builder<Module> b(std::forward<Args>(args)...);
+        return b.template create<Dce, DcePtr>(cfg);
+    }
+};
+
+/**
+ * @}
+ */
+
+} // namespace esp_modem::dce_factory
+
+
+#endif // _ESP_MODEM_DCE_FACTORY_HPP_

components/esp_modem/include/cxx_include/esp_modem_dce_module.hpp

@@ -0,0 +1,150 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_DCE_MODULE_
+#define _ESP_MODEM_DCE_MODULE_
+
+#include <memory>
+#include <utility>
+#include "generate/esp_modem_command_declare.inc"
+#include "cxx_include/esp_modem_command_library.hpp"
+#include "cxx_include/esp_modem_types.hpp"
+#include "esp_modem_dce_config.h"
+
+namespace esp_modem {
+
+/**
+ * @defgroup ESP_MODEM_MODULE
+ * @brief Definition of modules representing specific modem devices
+ */
+
+/** @addtogroup ESP_MODEM_MODULE
+* @{
+*/
+
+enum class command_result;
+class DTE;
+struct PdpContext;
+
+/**
+ * @brief This is a basic building block for custom modules as well as for the supported modules in the esp-modem component
+ * It derives from the ModuleIf.
+ */
+class GenericModule: public ModuleIf {
+public:
+    /**
+     * @brief We can construct a generic device with an existent DTE and it's configuration
+     * The configuration could be either the dce-config struct or just a pdp context
+     */
+    explicit GenericModule(std::shared_ptr<DTE> dte, std::unique_ptr<PdpContext> pdp):
+            dte(std::move(dte)), pdp(std::move(pdp)) {}
+    explicit GenericModule(std::shared_ptr<DTE> dte, const esp_modem_dce_config* config);
+
+    /**
+     * @brief This is a mandatory method for ModuleIf class, which sets up the device
+     * to be able to connect to the network. This typically consists of setting basic
+     * communication parameters and setting the PDP (defining logical access point
+     * to cellular network)
+     */
+    bool setup_data_mode() override
+    {
+        if (set_echo(false) != command_result::OK)
+            return false;
+        if (set_pdp_context(*pdp) != command_result::OK)
+            return false;
+        return true;
+    }
+
+    /**
+     * @brief This is a mandatory method of ModuleIf class, which defines
+     * basic commands for switching between DATA, COMMAND and CMUX modes
+     */
+    bool set_mode(modem_mode mode) override
+    {
+        if (mode == modem_mode::DATA_MODE) {
+            if (set_data_mode() != command_result::OK)
+                return resume_data_mode() == command_result::OK;
+            return true;
+        } else if (mode == modem_mode::COMMAND_MODE) {
+            return set_command_mode() == command_result::OK;
+        } else if (mode == modem_mode::CMUX_MODE) {
+            return set_cmux() == command_result::OK;
+        }
+        return true;
+    }
+
+    /**
+     * @brief Additional method providing runtime configuration of PDP context
+     */
+    void configure_pdp_context(std::unique_ptr<PdpContext> new_pdp)
+    {
+        pdp = std::move(new_pdp);
+    }
+
+    /**
+     * @brief Common DCE commands generated from the API AT list
+     */
+#define ESP_MODEM_DECLARE_DCE_COMMAND(name, return_type, num, ...) \
+    virtual return_type name(__VA_ARGS__);
+
+    DECLARE_ALL_COMMAND_APIS(virtual return_type name(...); )
+
+#undef ESP_MODEM_DECLARE_DCE_COMMAND
+
+
+protected:
+    std::shared_ptr<DTE> dte;         /*!< Generic device needs the DTE as a channel talk to the module using AT commands */
+    std::unique_ptr<PdpContext> pdp;  /*!< It also needs a PDP data, const information used for setting up cellular network */
+};
+
+// Definitions of other supported modules with some specific commands overwritten
+
+/**
+ * @brief Specific definition of the SIM7600 module
+ */
+class SIM7600: public GenericModule {
+    using GenericModule::GenericModule;
+public:
+    command_result get_module_name(std::string& name) override;
+    command_result get_battery_status(int& voltage, int &bcs, int &bcl) override;
+    command_result power_down() override;
+};
+
+/**
+ * @brief Specific definition of the SIM800 module
+ */
+class SIM800: public GenericModule {
+    using GenericModule::GenericModule;
+public:
+    command_result get_module_name(std::string& name) override;
+    command_result power_down() override;
+    command_result set_data_mode() override;
+};
+
+/**
+ * @brief Specific definition of the BG96 module
+ */
+class BG96: public GenericModule {
+    using GenericModule::GenericModule;
+public:
+    command_result get_module_name(std::string& name) override;
+};
+
+/**
+ * @}
+ */
+
+} // namespace esp_modem
+
+#endif // _ESP_MODEM_DCE_MODULE_

components/esp_modem/include/cxx_include/esp_modem_dte.hpp

@@ -0,0 +1,121 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_DTE_HPP_
+#define _ESP_MODEM_DTE_HPP_
+
+#include <memory>
+#include <cstddef>
+#include <cstdint>
+#include <utility>
+#include "cxx_include/esp_modem_primitives.hpp"
+#include "cxx_include/esp_modem_terminal.hpp"
+#include "cxx_include/esp_modem_cmux.hpp"
+#include "cxx_include/esp_modem_types.hpp"
+
+struct esp_modem_dte_config;
+
+namespace esp_modem {
+
+/**
+ * @defgroup ESP_MODEM_DTE
+ * @brief Definition of DTE and related classes
+ */
+/** @addtogroup ESP_MODEM_DTE
+* @{
+*/
+
+/**
+ * DTE (Data Terminal Equipment) class
+ */
+class DTE : public CommandableIf {
+public:
+
+    /**
+     * @brief Creates a DTE instance from the terminal
+     * @param config DTE config structure
+     * @param t unique-ptr to Terminal
+     */
+    explicit DTE(const esp_modem_dte_config *config, std::unique_ptr<Terminal> t);
+    explicit DTE(std::unique_ptr<Terminal> t);
+
+    ~DTE() = default;
+
+    /**
+     * @brief Writing to the underlying terminal
+     * @param data Data pointer to write
+     * @param len Data len to write
+     * @return number of bytes written
+     */
+    int write(uint8_t *data, size_t len);
+
+    /**
+     * @brief Reading from the underlying terminal
+     * @param d Returning the data pointer of the received payload
+     * @param len Length of the data payload
+     * @return number of bytes read
+     */
+    int read(uint8_t **d, size_t len);
+
+    /**
+     * @brief Sets read callback with valid data and length
+     * @param f Function to be called on data available
+     */
+    void set_read_cb(std::function<bool(uint8_t *data, size_t len)> f);
+
+    /**
+     * @brief Sets the DTE to desired mode (Command/Data/Cmux)
+     * @param m Desired operation mode
+     * @return true on success
+     */
+    [[nodiscard]] bool set_mode(modem_mode m);
+
+    /**
+     * @brief Sends command and provides callback with responding line
+     * @param command String parameter representing command
+     * @param got_line Function to be called after line available as a response
+     * @param time_ms Time in ms to wait for the answer
+     * @return OK, FAIL, TIMEOUT
+     */
+    command_result command(const std::string &command, got_line_cb got_line, uint32_t time_ms) override;
+
+    /**
+     * @brief Sends the command (same as above) but with a specific separator
+     */
+    command_result command(const std::string &command, got_line_cb got_line, uint32_t time_ms, char separator) override;
+
+private:
+    static const size_t GOT_LINE = SignalGroup::bit0;       /*!< Bit indicating response available */
+
+    [[nodiscard]] bool setup_cmux();                         /*!< Internal setup of CMUX mode */
+
+    Lock lock{};                                            /*!< Locks DTE operations */
+    size_t buffer_size;                                      /*!< Size of available DTE buffer */
+    size_t consumed;                                         /*!< Indication of already processed portion in DTE buffer */
+    std::unique_ptr<uint8_t[]> buffer;                       /*!< DTE buffer */
+    std::unique_ptr<Terminal> term;                          /*!< Primary terminal for this DTE */
+    Terminal *command_term;                                  /*!< Reference to the terminal used for sending commands */
+    std::unique_ptr<Terminal> other_term;                    /*!< Secondary terminal for this DTE */
+    modem_mode mode;                                         /*!< DTE operation mode */
+    SignalGroup signal;                                     /*!< Event group used to signal request-response operations */
+    std::function<bool(uint8_t *data, size_t len)> on_data;  /*!< on data callback for current terminal */
+};
+
+/**
+ * @}
+ */
+
+} // namespace esp_modem
+
+#endif // _ESP_MODEM_DTE_HPP_

components/esp_modem/include/cxx_include/esp_modem_exception.hpp

@@ -0,0 +1,66 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_EXCEPTION_HPP_
+#define _ESP_MODEM_EXCEPTION_HPP_
+
+#include <string>
+#include "esp_err.h"
+
+namespace esp_modem {
+
+#ifdef CONFIG_COMPILER_CXX_EXCEPTIONS
+#define THROW(exception) throw(exception)
+class esp_err_exception: virtual public std::exception {
+public:
+    explicit esp_err_exception(esp_err_t err): esp_err(err) {}
+    explicit esp_err_exception(std::string msg): esp_err(ESP_FAIL), message(std::move(msg)) {}
+    explicit esp_err_exception(std::string msg, esp_err_t err): esp_err(err), message(std::move(msg)) {}
+    virtual esp_err_t get_err_t() { return esp_err; }
+    ~esp_err_exception() noexcept override = default;
+    virtual const char* what() const noexcept {
+        return message.c_str();
+    }
+private:
+    esp_err_t esp_err;
+    std::string message;
+};
+#else
+#define THROW(exception) abort()
+#endif
+
+static inline void throw_if_false(bool condition, std::string message)
+{
+    if (!condition) {
+        THROW(esp_err_exception(std::move(message)));
+    }
+}
+
+static inline void throw_if_esp_fail(esp_err_t err, std::string message)
+{
+    if (err != ESP_OK) {
+        THROW(esp_err_exception(std::move(message), err));
+    }
+}
+
+static inline void throw_if_esp_fail(esp_err_t err)
+{
+    if (err != ESP_OK) {
+        THROW(esp_err_exception(err));
+    }
+}
+
+} // namespace esp_modem
+
+#endif //_ESP_MODEM_EXCEPTION_HPP_

components/esp_modem/include/cxx_include/esp_modem_netif.hpp

@@ -0,0 +1,89 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_NETIF_HPP
+#define _ESP_MODEM_NETIF_HPP
+
+#include <memory>
+#include <cstddef>
+#include "esp_netif.h"
+#include "cxx_include/esp_modem_primitives.hpp"
+
+namespace esp_modem {
+
+class DTE;
+class Netif;
+
+struct ppp_netif_driver {
+    esp_netif_driver_base_t base;
+    Netif *ppp;
+};
+
+/**
+ * @defgroup ESP_MODEM_NETIF
+ * @brief Network interface layer of the esp-modem
+ */
+
+/** @addtogroup ESP_MODEM_NETIF
+* @{
+*/
+
+/**
+ * @brief Network interface class responsible to glue the esp-netif to the modem's DCE
+ */
+class Netif {
+public:
+    explicit Netif(std::shared_ptr<DTE> e, esp_netif_t *netif);
+
+    ~Netif();
+
+    /**
+     * @brief Start the network interface
+     */
+    void start();
+
+    /**
+     * @brief Blocks until the network interface closes
+     */
+    void wait_until_ppp_exits();
+
+    /**
+     * @brief Stop the network interface
+     */
+    void stop();
+
+private:
+    void receive(uint8_t *data, size_t len);
+
+    static esp_err_t esp_modem_dte_transmit(void *h, void *buffer, size_t len);
+
+    static esp_err_t esp_modem_post_attach(esp_netif_t *esp_netif, void *args);
+
+    static void on_ppp_changed(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data);
+
+    std::shared_ptr<DTE> ppp_dte;
+    esp_netif_t *netif;
+    struct ppp_netif_driver driver{};
+    SignalGroup signal;
+    static const size_t PPP_STARTED = SignalGroup::bit0;
+    static const size_t PPP_EXIT = SignalGroup::bit1;
+};
+
+/**
+ * @}
+ */
+
+} // namespace esp_modem
+
+#endif // _ESP_MODEM_NETIF_HPP

components/esp_modem/include/cxx_include/esp_modem_primitives.hpp

@@ -0,0 +1,106 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_PRIMITIVES_HPP_
+#define _ESP_MODEM_PRIMITIVES_HPP_
+#include "esp_modem_exception.hpp"
+
+#if defined(CONFIG_IDF_TARGET_LINUX)
+#include <mutex>
+#include <thread>
+
+#else
+// forward declarations of FreeRTOS primitives
+struct QueueDefinition;
+typedef void * EventGroupHandle_t;
+#endif
+
+
+namespace esp_modem {
+
+// Forward declaration for both linux/FreeRTOS targets
+//
+using TaskFunction_t = void (*)(void*);
+#if !defined(CONFIG_IDF_TARGET_LINUX)
+struct Lock {
+    using MutexT = QueueDefinition*;
+    explicit Lock();
+    ~Lock();
+    void lock();
+    void unlock();
+private:
+    MutexT m{};
+};
+using TaskT = void*;
+using SignalT = void*;
+#else
+using Lock = std::mutex;
+struct SignalGroupInternal;
+using SignalT = std::unique_ptr<SignalGroupInternal>;
+using TaskT = std::thread;
+static constexpr uint32_t portMAX_DELAY = UINT32_MAX;
+#endif
+
+template<class T>
+class Scoped {
+public:
+    explicit Scoped(T &l):lock(l) { lock.lock(); }
+    ~Scoped() { lock.unlock(); }
+
+private:
+    T& lock;
+};
+
+class Task {
+public:
+    explicit Task(size_t stack_size, size_t priority, void *task_param, TaskFunction_t task_function);
+    ~Task();
+
+    static void Delete();
+    static void Relinquish();
+private:
+    TaskT task_handle;
+};
+
+
+class SignalGroup {
+public:
+    static constexpr size_t bit0 = 1 << 0;
+    static constexpr size_t bit1 = 1 << 1;
+    static constexpr size_t bit2 = 1 << 2;
+    static constexpr size_t bit3 = 1 << 3;
+
+    explicit SignalGroup();
+
+    void set(uint32_t bits);
+
+    void clear(uint32_t bits);
+
+    // waiting for all and clearing if set
+    bool wait(uint32_t flags, uint32_t time_ms);
+
+    bool is_any(uint32_t flags);
+
+    // waiting for any bit, not clearing them
+    bool wait_any(uint32_t flags, uint32_t time_ms);
+
+    ~SignalGroup();
+
+private:
+    SignalT event_group;
+};
+
+} // namespace esp_modem
+
+#endif // _ESP_MODEM_PRIMITIVES_HPP_

components/esp_modem/include/cxx_include/esp_modem_terminal.hpp

@@ -0,0 +1,89 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_TERMINAL_HPP_
+#define _ESP_MODEM_TERMINAL_HPP_
+
+#include <memory>
+#include <functional>
+#include <exception>
+#include <cstddef>
+#include <cstdint>
+#include <utility>
+#include "esp_err.h"
+#include "esp_modem_primitives.hpp"
+
+namespace esp_modem {
+
+/**
+ * @defgroup ESP_MODEM_TERMINAL
+ * @brief Definition of an abstract terminal to be attached to DTE class
+ */
+
+/** @addtogroup ESP_MODEM_TERMINAL
+* @{
+*/
+
+/**
+ * @brief Terminal errors
+ */
+enum class terminal_error {
+    BUFFER_OVERFLOW,
+    CHECKSUM_ERROR,
+    UNEXPECTED_CONTROL_FLOW,
+};
+
+/**
+ * @brief Terminal interface. All communication interfaces must comply this interface in order to be used as a DTE
+ */
+class Terminal {
+public:
+    virtual ~Terminal() = default;
+
+    void set_error_cb(std::function<void(terminal_error)> f) { on_error = std::move(f); }
+
+    virtual void set_read_cb(std::function<bool(uint8_t *data, size_t len)> f) { on_data = std::move(f); }
+
+    /**
+     * @brief Writes data to the terminal
+     * @param data Data pointer
+     * @param len Data len
+     * @return length of data written
+     */
+    virtual int write(uint8_t *data, size_t len) = 0;
+
+    /**
+     * @brief Read from the terminal. This function doesn't block, but return all available data.
+     * @param data Data pointer to store the read payload
+     * @param len Maximum data len to read
+     * @return length of data actually read
+     */
+    virtual int read(uint8_t *data, size_t len) = 0;
+
+    virtual void start() = 0;
+
+    virtual void stop() = 0;
+
+protected:
+    std::function<bool(uint8_t *data, size_t len)> on_data;
+    std::function<void(terminal_error)> on_error;
+};
+
+/**
+ * @}
+ */
+
+} // namespace esp_modem
+
+#endif // _ESP_MODEM_TERMINAL_HPP_

components/esp_modem/include/cxx_include/esp_modem_types.hpp

@@ -0,0 +1,107 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_TYPES_HPP_
+#define _ESP_MODEM_TYPES_HPP_
+
+#include <functional>
+#include <string>
+#include <cstddef>
+#include <cstdint>
+
+namespace esp_modem {
+
+/**
+ * @defgroup ESP_MODEM_TYPES
+ * @brief Basic type definitions used in esp-modem
+ */
+
+/** @addtogroup ESP_MODEM_TYPES
+* @{
+*/
+
+/**
+ * @brief Modem working mode
+ */
+enum class modem_mode {
+    UNDEF,
+    COMMAND_MODE, /*!< Command mode -- the modem is supposed to send AT commands in this mode  */
+    DATA_MODE,    /*!< Data mode -- the modem communicates with network interface on PPP protocol */
+    CMUX_MODE     /*!< CMUX (Multiplex mode) -- Simplified CMUX mode, which creates two virtual terminals,
+                   *  assigning one solely to command interface and the other  to the data mode */
+};
+
+/**
+ * @brief Module command result
+ */
+enum class command_result {
+    OK,             /*!< The command completed successfully */
+    FAIL,           /*!< The command explicitly failed */
+    TIMEOUT         /*!< The device didn't respond in the specified timeline */
+};
+
+typedef std::function<command_result(uint8_t *data, size_t len)> got_line_cb;
+
+/**
+ * @brief PDP context used for configuring and setting the data mode up
+ */
+struct PdpContext {
+    explicit PdpContext(std::string apn) : apn(std::move(apn)) {}
+    size_t context_id = 1;
+    std::string protocol_type = "IP";
+    std::string apn;
+};
+
+/**
+ * @brief Interface for classes eligible to send AT commands (Modules, DCEs, DTEs)
+ */
+class CommandableIf {
+public:
+    /**
+     * @brief Sends custom AT command
+     * @param command Command to be sent
+     * @param got_line callback if a line received
+     * @param time_ms timeout in milliseconds
+     * @return OK, FAIL or TIMEOUT
+     */
+    virtual command_result command(const std::string &command, got_line_cb got_line, uint32_t time_ms, const char separator) = 0;
+    virtual command_result command(const std::string &command, got_line_cb got_line, uint32_t time_ms) = 0;
+};
+
+/**
+ * @brief Interface for classes implementing a module for the modem
+ */
+class ModuleIf {
+public:
+    /**
+     * @brief Sets the data mode up (provides the necessary configuration to connect to the cellular network
+     * @return true on success
+     */
+    virtual bool setup_data_mode() = 0;
+
+    /**
+     * @brief Sets the operation mode
+     * @param mode Desired mode
+     * @return true on success
+     */
+    virtual bool set_mode(modem_mode mode) = 0;
+};
+
+/**
+ * @}
+ */
+
+} // namespace esp_modem
+
+#endif // _ESP_MODEM_TYPES_HPP_

components/esp_modem/include/esp_modem_api.h

@@ -0,0 +1,40 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_API_H_
+#define _ESP_MODEM_API_H_
+
+#include "esp_err.h"
+#include "generate/esp_modem_command_declare.inc"
+#include "esp_modem_c_api_types.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+#define ESP_MODEM_DECLARE_DCE_COMMAND(name, return_type, num, ...) \
+        esp_err_t esp_modem_ ## name(esp_modem_dce_t *dce, ##__VA_ARGS__);
+
+DECLARE_ALL_COMMAND_APIS(declares esp_modem_<API>(esp_modem_t * dce, ...);)
+
+#undef ESP_MODEM_DECLARE_DCE_COMMAND
+
+
+#ifdef __cplusplus
+}
+#endif
+
+
+#endif // _CLIENT_ESP_MODEM_API_H_

components/esp_modem/include/esp_modem_c_api_types.h

@@ -0,0 +1,102 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_C_API_TYPES_H_
+#define _ESP_MODEM_C_API_TYPES_H_
+
+#include "esp_modem_config.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct esp_modem_dce_wrap esp_modem_dce_t;
+
+struct PdpContext;
+
+/**
+ * @defgroup ESP_MODEM_C_API ESP_MODEM C API
+ * @brief Set of basic C API for ESP-MODEM
+ */
+/** @addtogroup ESP_MODEM_C_API
+ * @{
+ */
+
+/**
+ * @brief DCE mode: This enum is used to set desired operation mode of the DCE
+ */
+typedef enum esp_modem_dce_mode
+{
+    ESP_MODEM_MODE_COMMAND,  /**< Default mode after modem startup, used for sending AT commands */
+    ESP_MODEM_MODE_DATA,     /**< Used for switching to PPP mode for the modem to connect to a network */
+} esp_modem_dce_mode_t;
+
+/**
+ * @brief DCE devices: Enum list of supported devices
+ */
+typedef enum esp_modem_dce_device
+{
+    ESP_MODEM_DCE_GENETIC,  /**< The most generic device */
+    ESP_MODEM_DCE_SIM7600,
+    ESP_MODEM_DCE_BG96,
+    ESP_MODEM_DCE_SIM800,
+} esp_modem_dce_device_t;
+
+/**
+ * @brief Create a generic DCE handle for new modem API
+ *
+ * @param dte_config DTE configuration (UART config for now)
+ * @param dce_config DCE configuration
+ * @param netif Network interface handle for the data mode
+ *
+ * @return DCE pointer on success, NULL on failure
+ */
+esp_modem_dce_t *esp_modem_new(const esp_modem_dte_config_t *dte_config, const esp_modem_dce_config_t *dce_config, esp_netif_t *netif);
+
+/**
+ * @brief Create a DCE handle using the supplied device
+ *
+ * @param module Specific device for creating this DCE
+ * @param dte_config DTE configuration (UART config for now)
+ * @param dce_config DCE configuration
+ * @param netif Network interface handle for the data mode
+ *
+ * @return DCE pointer on success, NULL on failure
+ */
+esp_modem_dce_t *esp_modem_new_dev(esp_modem_dce_device_t module, const esp_modem_dte_config_t *dte_config, const esp_modem_dce_config_t *dce_config, esp_netif_t *netif);
+
+/**
+ * @brief Destroys modem's DCE handle
+ *
+ * @param dce DCE to destroy
+ */
+void esp_modem_destroy(esp_modem_dce_t * dce);
+
+/**
+ * @brief Set operation mode for this DCE
+ * @param dce Modem DCE handle
+ * @param mode Desired MODE
+ * @return ESP_OK on success, ESP_FAIL on failure
+ */
+esp_err_t esp_modem_set_mode(esp_modem_dce_t * dce, esp_modem_dce_mode_t mode);
+
+/**
+ * @}
+ */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif //_ESP_MODEM_C_API_TYPES_H_

components/esp_modem/include/esp_modem_config.h

@@ -0,0 +1,130 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_CONFIG_H_
+#define _ESP_MODEM_CONFIG_H_
+#include "driver/uart.h"
+#include "esp_modem_dce_config.h"
+
+/**
+ * @defgroup ESP_MODEM_CONFIG
+ * @brief Configuration structures for DTE and DCE
+ */
+
+/** @addtogroup ESP_MODEM_CONFIG
+ * @{
+ */
+
+/**
+ * @brief Modem flow control type
+ *
+ */
+typedef enum {
+    ESP_MODEM_FLOW_CONTROL_NONE = 0,
+    ESP_MODEM_FLOW_CONTROL_SW,
+    ESP_MODEM_FLOW_CONTROL_HW
+} esp_modem_flow_ctrl_t;
+
+/**
+ * @brief UART configuration structure
+ *
+ */
+struct esp_modem_uart_term_config {
+    uart_port_t port_num;           /*!< UART port number */
+    uart_word_length_t data_bits;   /*!< Data bits of UART */
+    uart_stop_bits_t stop_bits;     /*!< Stop bits of UART */
+    uart_parity_t parity;           /*!< Parity type */
+    esp_modem_flow_ctrl_t flow_control; /*!< Flow control type */
+    int baud_rate;             /*!< Communication baud rate */
+    int tx_io_num;                  /*!< TXD Pin Number */
+    int rx_io_num;                  /*!< RXD Pin Number */
+    int rts_io_num;                 /*!< RTS Pin Number */
+    int cts_io_num;                 /*!< CTS Pin Number */
+    int rx_buffer_size;             /*!< UART RX Buffer Size */
+    int tx_buffer_size;             /*!< UART TX Buffer Size */
+    int event_queue_size;           /*!< UART Event Queue Size, set to 0 if no event queue needed */
+};
+
+/**
+ * @brief Resources used by VFS terminal
+ *
+ */
+typedef enum {
+    ESP_MODEM_VFS_IS_EXTERN = 0,    /*!< External resource: internal VFS terminal takes no action to setup this */
+    ESP_MODEM_VFS_IS_UART,          /*!< VFS uses UART: internal VFS initializes UART based on esp_modem_uart_term_config */
+} esp_modem_vfs_resource_t;
+
+
+/**
+ * @brief VFS configuration structure
+ *
+ */
+struct esp_modem_vfs_term_config {
+    const char* dev_name;               /*!< VFS device name, e.g. /dev/uart/n */
+    esp_modem_vfs_resource_t resource;  /*!< Underlying device which gets initialized during VFS init */
+};
+
+/**
+ * @brief Complete DTE configuration structure
+ *
+ * Note that the generic part is common for DTE and its SW resources
+ * The following portions for config is dedicated to the chosen HW resource
+ * used as a communication terminal for this DTE
+ */
+struct esp_modem_dte_config {
+    size_t dte_buffer_size;                             /*!< DTE buffer size */
+    uint32_t task_stack_size;                           /*!< Terminal task stack size */
+    int task_priority;                                  /*!< Terminal task priority */
+    struct esp_modem_uart_term_config uart_config;      /*!< Configuration for UART Terminal */
+    struct esp_modem_vfs_term_config vfs_config;        /*!< Configuration for VFS Terminal */
+};
+
+
+/**
+ * @brief ESP Modem DTE Default Configuration
+ *
+ */
+#define ESP_MODEM_DTE_DEFAULT_CONFIG() \
+    {                                  \
+        .dte_buffer_size = 512,        \
+        .task_stack_size = 4096, \
+        .task_priority = 5,      \
+        .uart_config = {               \
+            .port_num = UART_NUM_1,                 \
+            .data_bits = UART_DATA_8_BITS,          \
+            .stop_bits = UART_STOP_BITS_1,          \
+            .parity = UART_PARITY_DISABLE,          \
+            .flow_control = ESP_MODEM_FLOW_CONTROL_NONE,\
+            .baud_rate = 115200,                    \
+            .tx_io_num = 25,                        \
+            .rx_io_num = 26,                        \
+            .rts_io_num = 27,                       \
+            .cts_io_num = 23,                       \
+            .rx_buffer_size = 4096,                 \
+            .tx_buffer_size = 512,                  \
+            .event_queue_size = 30,                 \
+       },                                           \
+       .vfs_config = {                              \
+            .dev_name = "/null",                    \
+            .resource =  ESP_MODEM_VFS_IS_EXTERN    \
+       }\
+    }
+
+typedef struct esp_modem_dte_config esp_modem_dte_config_t;
+
+/**
+ * @}
+ */
+
+#endif // _ESP_MODEM_CONFIG_H_

components/esp_modem/include/esp_modem_dce_config.h

@@ -0,0 +1,45 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_DCE_CONFIG_H_
+#define _ESP_MODEM_DCE_CONFIG_H_
+
+/** @addtogroup ESP_MODEM_CONFIG
+ * @{
+ */
+
+/**
+ * @brief ESP Modem DCE Default Configuration
+ *
+ */
+#define ESP_MODEM_DCE_DEFAULT_CONFIG(APN)       \
+    {                                           \
+        .apn = APN                              \
+    }
+
+typedef struct esp_modem_dce_config esp_modem_dce_config_t;
+
+/**
+ * @brief DCE configuration structure
+ */
+struct esp_modem_dce_config {
+    const char* apn;  /*!< APN: Logical name of the Access point */
+};
+
+/**
+ * @}
+ */
+
+
+#endif // _ESP_MODEM_DCE_CONFIG_H_

components/esp_modem/include/generate/esp_modem_command_declare.inc

@@ -0,0 +1,234 @@
+// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP_MODEM_COMMAND_DECLARE_INC_
+#define _ESP_MODEM_COMMAND_DECLARE_INC_
+
+
+// Parameters
+// * handle different parameters for C++ and C API
+// * make parameter unique names, so they could be easily referenced and forwarded
+#define _ARG(param, name) param
+#define INT_IN(param, name) int  _ARG(param, name)
+#ifdef __cplusplus
+#include <string>
+#define STRING_IN(param, name) const std::string& _ARG(param, name)
+#define STRING_OUT(param, name) std::string& _ARG(param, name)
+#define BOOL_IN(param, name) const bool  _ARG(param, name)
+#define BOOL_OUT(param, name) bool&  _ARG(param, name)
+#define INT_OUT(param, name) int&  _ARG(param, name)
+
+#define STRUCT_OUT(struct_name, x)  struct_name& x
+#else
+#define STRING_IN(param, name) const char* _ARG(param, name)
+#define STRING_OUT(param, name) char* _ARG(param, name)
+#define BOOL_IN(param, name) const bool _ARG(param, name)
+#define BOOL_OUT(param, name) bool* _ARG(param, name)
+#define INT_OUT(param, name) int* _ARG(param, name)
+#define STRUCT_OUT(struct_name, x)  struct struct_name* x
+#endif
+
+#define DECLARE_ALL_COMMAND_APIS(...) \
+/**
+ * @brief Sends the initial AT sequence to sync up with the device
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(sync, command_result, 0) \
+/**
+ * @brief Reads the operator name
+ * @param[out] name module name
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(get_operator_name, command_result, 1, STRING_OUT(x, name)) \
+    \
+/**
+ * @brief Stores current user profile
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(store_profile, command_result, 0) \
+    \
+/**
+ * @brief Sets the supplied PIN code
+ * @param[in] pin Pin
+ * @return OK, FAIL or TIMEOUT
+ */\
+ESP_MODEM_DECLARE_DCE_COMMAND(set_pin,  command_result, 1, STRING_IN(x, pin)) \
+    \
+/**
+ * @brief Checks if the SIM needs a PIN
+ * @param[out] pin_ok true if the SIM card doesn't need a PIN to unlock
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(read_pin, command_result, 1, BOOL_OUT(x, pin_ok)) \
+    \
+/**
+ * @brief Sets echo mode
+ * @param[in] echo_on true if echo mode on (repeats the commands)
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(set_echo, command_result, 1, BOOL_IN(x, echo_on)) \
+    \
+/**
+ * @brief Sets the Txt or Pdu mode for SMS (only txt is supported)
+ * @param[in] txt true if txt mode
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(sms_txt_mode, command_result, 1, BOOL_IN(x, txt)) \
+    \
+/**
+ * @brief Sets the default (GSM) charater set
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(sms_character_set, command_result, 0) \
+    \
+/**
+ * @brief Sends SMS message in txt mode
+ * @param[in] number Phone number to send the message to
+ * @param[in] message Text message to be sent
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(send_sms, command_result, 2, STRING_IN(x, number), STRING_IN(y, message)) \
+    \
+/**
+ * @brief Resumes data mode (Switches back to th data mode, which was temporarily suspended)
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(resume_data_mode, command_result, 0) \
+    \
+/**
+ * @brief Sets php context
+ * @param[in] x PdP context struct to setup modem cellular connection
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(set_pdp_context, command_result, 1, STRUCT_OUT(PdpContext, x)) \
+    \
+/**
+ * @brief Switches to the command mode
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(set_command_mode, command_result, 0) \
+    \
+/**
+ * @brief Switches to the CMUX mode
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(set_cmux, command_result, 0) \
+    \
+/**
+ * @brief Reads the IMSI number
+ * @param[out] imsi Module's IMSI number
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(get_imsi, command_result, 1, STRING_OUT(x, imsi)) \
+    \
+/**
+ * @brief Reads the IMEI number
+ * @param[out] imei Module's IMEI number
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(get_imei, command_result, 1, STRING_OUT(x, imei)) \
+    \
+/**
+ * @brief Reads the module name
+ * @param[out] name module name
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(get_module_name, command_result, 1, STRING_OUT(x, name)) \
+    \
+/**
+ * @brief Sets the modem to data mode
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(set_data_mode, command_result, 0) \
+    \
+/**
+ * @brief Get Signal quality
+ * @param[out] rssi signal strength indication
+ * @param[out] ber channel bit error rate
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(get_signal_quality, command_result, 2, INT_OUT(x, rssi), INT_OUT(y, ber)) \
+    \
+/**
+ * @brief Sets HW control flow
+ * @param[in] dce_flow 0=none, 2=RTS hw flow control of DCE
+ * @param[in] dte_flow 0=none, 2=CTS hw flow control of DTE
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(set_flow_control, command_result, 2, INT_IN(x, dce_flow), INT_IN(y, dte_flow)) \
+    \
+/**
+ * @brief Hangs up current data call
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(hang_up, command_result, 0) \
+    \
+/**
+ * @brief Get voltage levels of modem power up circuitry
+ * @param[out] voltage Current status in mV
+ * @param[out] bcs charge status (-1-Not available, 0-Not charging, 1-Charging, 2-Charging done)
+ * @param[out] bcl 1-100% battery capacity, -1-Not available
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(get_battery_status, command_result, 3, INT_OUT(x, voltage), INT_OUT(y, bcs), INT_OUT(z, bcl)) \
+    \
+/**
+ * @brief Power down the module
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(power_down, command_result, 0) \
+    \
+/**
+ * @brief Reset the module
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(reset, command_result, 0)\
+    \
+/**
+ * @brief Configures the baudrate
+ * @param[in] baud Desired baud rate of the DTE
+ * @return OK, FAIL or TIMEOUT
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(set_baud, command_result, 1, INT_IN(x, baud))
+
+
+#ifdef GENERATE_DOCS
+// cat ../include/generate/esp_modem_command_declare.inc | clang++ -E -P -CC  -xc++ -I../include -DGENERATE_DOCS  - | sed -n '1,/DCE command documentation/!p'
+// cat ../include/generate/esp_modem_command_declare.inc | clang -E -P -CC  -xc -I../include -DGENERATE_DOCS  - | sed -n '1,/DCE command documentation/!p' > c_api.h
+// cat ../include/generate/esp_modem_command_declare.inc | clang -E -P  -xc -I../include -DGENERATE_DOCS -DGENERATE_RST_LINKS - | sed 's/NL/\n/g' > cxx_api_links.rst
+
+// call parametrs by names for documentation
+#undef _ARG
+#define _ARG(param, name) name
+//  --- DCE command documentation starts here ---
+#ifdef __cplusplus
+class esp_modem::DCE: public DCE_T<GenericModule> {
+public:
+    using DCE_T<GenericModule>::DCE_T;
+#define ESP_MODEM_DECLARE_DCE_COMMAND(name, return_type, TEMPLATE_ARG, ...) return_type name (__VA_ARGS__);
+#elif defined(GENERATE_RST_LINKS)
+#define ESP_MODEM_DECLARE_DCE_COMMAND(name, return_type, TEMPLATE_ARG, ...) NL- :cpp:func:`esp_modem::DCE::name`
+#else
+#define ESP_MODEM_DECLARE_DCE_COMMAND(name, return_type, TEMPLATE_ARG, ...) return_type esp_modem_ ## name (__VA_ARGS__);
+#endif
+
+DECLARE_ALL_COMMAND_APIS()
+
+#ifdef __cplusplus
+};
+#endif
+
+#endif
+
+#endif // _ESP_MODEM_COMMAND_DECLARE_INC_