| /* Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "nacl_io_demo.h" |
| |
| #include <assert.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <pthread.h> |
| |
| #include "ppapi/c/pp_errors.h" |
| #include "ppapi/c/pp_module.h" |
| #include "ppapi/c/ppb.h" |
| #include "ppapi/c/ppb_instance.h" |
| #include "ppapi/c/ppb_messaging.h" |
| #include "ppapi/c/ppb_var.h" |
| #include "ppapi/c/ppp.h" |
| #include "ppapi/c/ppp_instance.h" |
| #include "ppapi/c/ppp_messaging.h" |
| #include "nacl_io/nacl_io.h" |
| |
| #include "handlers.h" |
| #include "queue.h" |
| |
| #define MIN(a, b) (((a) < (b)) ? (a) : (b)) |
| |
| #if defined(WIN32) |
| #define va_copy(d, s) ((d) = (s)) |
| #endif |
| |
| typedef struct { |
| const char* name; |
| HandleFunc function; |
| } FuncNameMapping; |
| |
| static PP_Instance g_instance = 0; |
| static PPB_GetInterface get_browser_interface = NULL; |
| static PPB_Messaging* ppb_messaging_interface = NULL; |
| static PPB_Var* ppb_var_interface = NULL; |
| |
| static FuncNameMapping g_function_map[] = { |
| {"fopen", HandleFopen}, |
| {"fwrite", HandleFwrite}, |
| {"fread", HandleFread}, |
| {"fseek", HandleFseek}, |
| {"fclose", HandleFclose}, |
| {"stat", HandleStat}, |
| {"opendir", HandleOpendir}, |
| {"readdir", HandleReaddir}, |
| {"closedir", HandleClosedir}, |
| {"mkdir", HandleMkdir}, |
| {NULL, NULL}, |
| }; |
| |
| /** A handle to the thread the handles messages. */ |
| static pthread_t g_handle_message_thread; |
| |
| /** |
| * Create a new PP_Var from a C string. |
| * @param[in] str The string to convert. |
| * @return A new PP_Var with the contents of |str|. */ |
| struct PP_Var CStrToVar(const char* str) { |
| if (ppb_var_interface != NULL) { |
| return ppb_var_interface->VarFromUtf8(str, strlen(str)); |
| } |
| return PP_MakeUndefined(); |
| } |
| |
| /** |
| * Printf to a newly allocated C string. |
| * @param[in] format A printf format string. |
| * @param[in] args The printf arguments. |
| * @return The newly constructed string. Caller takes ownership. */ |
| char* VprintfToNewString(const char* format, va_list args) { |
| va_list args_copy; |
| int length; |
| char* buffer; |
| int result; |
| |
| va_copy(args_copy, args); |
| length = vsnprintf(NULL, 0, format, args); |
| buffer = (char*)malloc(length + 1); /* +1 for NULL-terminator. */ |
| result = vsnprintf(&buffer[0], length + 1, format, args_copy); |
| assert(result == length); |
| return buffer; |
| } |
| |
| /** |
| * Printf to a newly allocated C string. |
| * @param[in] format A print format string. |
| * @param[in] ... The printf arguments. |
| * @return The newly constructed string. Caller takes ownership. */ |
| char* PrintfToNewString(const char* format, ...) { |
| va_list args; |
| char* result; |
| va_start(args, format); |
| result = VprintfToNewString(format, args); |
| va_end(args); |
| return result; |
| } |
| |
| /** |
| * Printf to a new PP_Var. |
| * @param[in] format A print format string. |
| * @param[in] ... The printf arguments. |
| * @return A new PP_Var. */ |
| struct PP_Var PrintfToVar(const char* format, ...) { |
| if (ppb_var_interface != NULL) { |
| char* string; |
| va_list args; |
| struct PP_Var var; |
| |
| va_start(args, format); |
| string = VprintfToNewString(format, args); |
| va_end(args); |
| |
| var = ppb_var_interface->VarFromUtf8(string, strlen(string)); |
| free(string); |
| |
| return var; |
| } |
| |
| return PP_MakeUndefined(); |
| } |
| |
| /** |
| * Convert a PP_Var to a C string, given a buffer. |
| * @param[in] var The PP_Var to convert. |
| * @param[out] buffer The buffer to write to. |
| * @param[in] length The length of |buffer|. |
| * @return The number of characters written. */ |
| uint32_t VarToCStr(struct PP_Var var, char* buffer, uint32_t length) { |
| if (ppb_var_interface != NULL) { |
| uint32_t var_length; |
| const char* str = ppb_var_interface->VarToUtf8(var, &var_length); |
| /* str is NOT NULL-terminated. Copy using memcpy. */ |
| uint32_t min_length = MIN(var_length, length - 1); |
| memcpy(buffer, str, min_length); |
| buffer[min_length] = 0; |
| |
| return min_length; |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * Given a message from JavaScript, parse it for functions and parameters. |
| * |
| * The format of the message is: |
| * function, param1, param2, param3, etc. |
| * where each element is separated by the \1 character. |
| * |
| * e.g. |
| * "function\1first parameter\1second parameter" |
| * |
| * How to use: |
| * char* function; |
| * char* params[4]; |
| * int num_params = ParseMessage(msg, &function, ¶ms, 4); |
| * |
| * @param[in, out] message The message to parse. This string is modified |
| * in-place. |
| * @param[out] out_function The function name. |
| * @param[out] out_params An array of strings, one for each parameter parsed. |
| * @param[in] max_params The maximum number of parameters to parse. |
| * @return The number of parameters parsed. */ |
| static size_t ParseMessage(char* message, |
| char** out_function, |
| char** out_params, |
| size_t max_params) { |
| char* separator; |
| char* param_start; |
| size_t num_params = 0; |
| |
| /* Parse the message: function\1param1\1param2\1param3,... */ |
| *out_function = &message[0]; |
| |
| separator = strchr(message, 1); |
| if (!separator) { |
| return num_params; |
| } |
| |
| *separator = 0; /* NULL-terminate function. */ |
| |
| while (separator && num_params < max_params) { |
| param_start = separator + 1; |
| separator = strchr(param_start, 1); |
| if (separator) { |
| *separator = 0; |
| out_params[num_params++] = param_start; |
| } |
| } |
| |
| out_params[num_params++] = param_start; |
| |
| return num_params; |
| } |
| |
| /** |
| * Given a function name, look up its handler function. |
| * @param[in] function_name The function name to look up. |
| * @return The handler function mapped to |function_name|. */ |
| static HandleFunc GetFunctionByName(const char* function_name) { |
| FuncNameMapping* map_iter = g_function_map; |
| for (; map_iter->name; ++map_iter) { |
| if (strcmp(map_iter->name, function_name) == 0) { |
| return map_iter->function; |
| } |
| } |
| |
| return NULL; |
| } |
| |
| /** Handle as message from JavaScript on the worker thread. |
| * |
| * @param[in] message The message to parse and handle. */ |
| static void HandleMessage(char* message) { |
| char* function_name; |
| char* params[MAX_PARAMS]; |
| size_t num_params; |
| char* output = NULL; |
| int result; |
| HandleFunc function; |
| |
| num_params = ParseMessage(message, &function_name, ¶ms[0], MAX_PARAMS); |
| |
| function = GetFunctionByName(function_name); |
| if (!function) { |
| /* Function name wasn't found. Error. */ |
| ppb_messaging_interface->PostMessage( |
| g_instance, |
| PrintfToVar("Error: Unknown function \"%s\"", function_name)); |
| return; |
| } |
| |
| /* Function name was found, call it. */ |
| result = (*function)(num_params, ¶ms[0], &output); |
| if (result != 0) { |
| /* Error. */ |
| struct PP_Var var; |
| if (output != NULL) { |
| var = PrintfToVar("Error: Function \"%s\" returned error %d. " |
| "Additional output: %s", |
| function_name, |
| result, |
| output); |
| free(output); |
| } else { |
| var = PrintfToVar( |
| "Error: Function \"%s\" returned error %d.", function_name, result); |
| } |
| |
| /* Post the error to JavaScript, so the user can see it. */ |
| ppb_messaging_interface->PostMessage(g_instance, var); |
| return; |
| } |
| |
| if (output != NULL) { |
| /* Function returned an output string. Send it to JavaScript. */ |
| ppb_messaging_interface->PostMessage(g_instance, CStrToVar(output)); |
| free(output); |
| } |
| } |
| |
| /** A worker thread that handles messages from JavaScript. |
| * @param[in] user_data Unused. |
| * @return unused. */ |
| void* HandleMessageThread(void* user_data) { |
| while (1) { |
| char* message = DequeueMessage(); |
| HandleMessage(message); |
| free(message); |
| } |
| } |
| |
| static PP_Bool Instance_DidCreate(PP_Instance instance, |
| uint32_t argc, |
| const char* argn[], |
| const char* argv[]) { |
| g_instance = instance; |
| nacl_io_init_ppapi(instance, get_browser_interface); |
| |
| // By default, nacl_io mounts / to pass through to the original NaCl |
| // filesystem (which doesn't do much). Let's remount it to a memfs |
| // filesystem. |
| umount("/"); |
| mount("", "/", "memfs", 0, ""); |
| |
| mount("", /* source */ |
| "/persistent", /* target */ |
| "html5fs", /* filesystemtype */ |
| 0, /* mountflags */ |
| "type=PERSISTENT,expected_size=1048576"); /* data */ |
| |
| mount("", /* source. Use relative URL */ |
| "/http", /* target */ |
| "httpfs", /* filesystemtype */ |
| 0, /* mountflags */ |
| ""); /* data */ |
| |
| pthread_create(&g_handle_message_thread, NULL, &HandleMessageThread, NULL); |
| InitializeMessageQueue(); |
| |
| return PP_TRUE; |
| } |
| |
| static void Instance_DidDestroy(PP_Instance instance) {} |
| |
| static void Instance_DidChangeView(PP_Instance instance, |
| PP_Resource view_resource) {} |
| |
| static void Instance_DidChangeFocus(PP_Instance instance, PP_Bool has_focus) {} |
| |
| static PP_Bool Instance_HandleDocumentLoad(PP_Instance instance, |
| PP_Resource url_loader) { |
| /* NaCl modules do not need to handle the document load function. */ |
| return PP_FALSE; |
| } |
| |
| static void Messaging_HandleMessage(PP_Instance instance, |
| struct PP_Var message) { |
| char buffer[1024]; |
| VarToCStr(message, &buffer[0], 1024); |
| if (!EnqueueMessage(strdup(buffer))) { |
| struct PP_Var var; |
| var = PrintfToVar( |
| "Warning: dropped message \"%s\" because the queue was full.", message); |
| ppb_messaging_interface->PostMessage(g_instance, var); |
| } |
| } |
| |
| PP_EXPORT int32_t PPP_InitializeModule(PP_Module a_module_id, |
| PPB_GetInterface get_browser) { |
| get_browser_interface = get_browser; |
| ppb_messaging_interface = |
| (PPB_Messaging*)(get_browser(PPB_MESSAGING_INTERFACE)); |
| ppb_var_interface = (PPB_Var*)(get_browser(PPB_VAR_INTERFACE)); |
| return PP_OK; |
| } |
| |
| PP_EXPORT const void* PPP_GetInterface(const char* interface_name) { |
| if (strcmp(interface_name, PPP_INSTANCE_INTERFACE) == 0) { |
| static PPP_Instance instance_interface = { |
| &Instance_DidCreate, |
| &Instance_DidDestroy, |
| &Instance_DidChangeView, |
| &Instance_DidChangeFocus, |
| &Instance_HandleDocumentLoad, |
| }; |
| return &instance_interface; |
| } else if (strcmp(interface_name, PPP_MESSAGING_INTERFACE) == 0) { |
| static PPP_Messaging messaging_interface = { |
| &Messaging_HandleMessage, |
| }; |
| return &messaging_interface; |
| } |
| return NULL; |
| } |
| |
| PP_EXPORT void PPP_ShutdownModule() {} |