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Diffstat (limited to '')
| -rw-r--r-- | src/output/httpd_client.c | 523 |
1 files changed, 523 insertions, 0 deletions
diff --git a/src/output/httpd_client.c b/src/output/httpd_client.c new file mode 100644 index 000000000..fb3f0548a --- /dev/null +++ b/src/output/httpd_client.c @@ -0,0 +1,523 @@ +/* + * Copyright (C) 2003-2009 The Music Player Daemon Project + * http://www.musicpd.org + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include "httpd_client.h" +#include "httpd_internal.h" +#include "fifo_buffer.h" +#include "page.h" + +#include <stdbool.h> +#include <assert.h> +#include <string.h> + +struct httpd_client { + /** + * The httpd output object this client is connected to. + */ + struct httpd_output *httpd; + + /** + * The TCP socket. + */ + GIOChannel *channel; + + /** + * The GLib main loop source id for reading from the socket, + * and to detect errors. + */ + guint read_source_id; + + /** + * The GLib main loop source id for writing to the socket. If + * 0, then there is no event source currently (because there + * are no queued pages). + */ + guint write_source_id; + + /** + * For buffered reading. This pointer is only valid while the + * HTTP request is read. + */ + struct fifo_buffer *input; + + /** + * The current state of the client. + */ + enum { + /** reading the request line */ + REQUEST, + + /** reading the request headers */ + HEADERS, + + /** sending the HTTP response */ + RESPONSE, + } state; + + /** + * A queue of #page objects to be sent to the client. + */ + GQueue *pages; + + /** + * The #page which is currently being sent to the client. + */ + struct page *current_page; + + /** + * The amount of bytes which were already sent from + * #current_page. + */ + size_t current_position; +}; + +static void +httpd_client_unref_page(gpointer data, G_GNUC_UNUSED gpointer user_data) +{ + struct page *page = data; + + page_unref(page); +} + +void +httpd_client_free(struct httpd_client *client) +{ + if (client->state == RESPONSE) { + if (client->write_source_id != 0) + g_source_remove(client->write_source_id); + + if (client->current_page != NULL) + page_unref(client->current_page); + + g_queue_foreach(client->pages, httpd_client_unref_page, NULL); + g_queue_free(client->pages); + } else + fifo_buffer_free(client->input); + + g_source_remove(client->read_source_id); + g_io_channel_unref(client->channel); + g_free(client); +} + +/** + * Frees the client and removes it from the server's client list. + */ +static void +httpd_client_close(struct httpd_client *client) +{ + httpd_output_remove_client(client->httpd, client); + httpd_client_free(client); +} + +/** + * Switch the client to the "RESPONSE" state. + */ +static void +httpd_client_begin_response(struct httpd_client *client) +{ + client->state = RESPONSE; + client->write_source_id = 0; + client->pages = g_queue_new(); + client->current_page = NULL; + + httpd_output_send_header(client->httpd, client); +} + +/** + * Handle a line of the HTTP request. + */ +static bool +httpd_client_handle_line(struct httpd_client *client, const char *line) +{ + assert(client->state != RESPONSE); + + if (client->state == REQUEST) { + if (strncmp(line, "GET /", 5) != 0) { + /* only GET is supported */ + g_warning("malformed request line from client"); + return false; + } + + line = strchr(line + 5, ' '); + if (line == NULL || strncmp(line + 1, "HTTP/", 5) != 0) { + /* HTTP/0.9 without request headers */ + httpd_client_begin_response(client); + return true; + } + + /* after the request line, request headers follow */ + client->state = HEADERS; + return true; + } else { + if (*line == 0) { + /* empty line: request is finished */ + httpd_client_begin_response(client); + return true; + } + + /* expect more request headers */ + return true; + } +} + +/** + * Check if a complete line of input is present in the input buffer, + * and duplicates it. It is removed from the input buffer. The + * return value has to be freed with g_free(). + */ +static char * +httpd_client_read_line(struct httpd_client *client) +{ + const char *p, *newline; + size_t length; + char *line; + + p = fifo_buffer_read(client->input, &length); + if (p == NULL) + /* empty input buffer */ + return NULL; + + newline = memchr(p, '\n', length); + if (newline == NULL) + /* incomplete line */ + return NULL; + + line = g_strndup(p, newline - p); + fifo_buffer_consume(client->input, newline - p + 1); + + /* remove trailing whitespace (e.g. '\r') */ + return g_strchomp(line); +} + +/** + * Sends the status line and response headers to the client. + */ +static bool +httpd_client_send_response(struct httpd_client *client) +{ + char buffer[1024]; + GError *error = NULL; + GIOStatus status; + gsize bytes_written; + + assert(client->state == RESPONSE); + + g_snprintf(buffer, sizeof(buffer), + "HTTP/1.1 200 OK\r\n" + "Content-Type: %s\r\n" + "Connection: close\r\n" + "Pragma: no-cache\r\n" + "Cache-Control: no-cache, no-store\r\n" + "\r\n", + client->httpd->content_type); + + status = g_io_channel_write_chars(client->channel, + buffer, strlen(buffer), + &bytes_written, &error); + switch (status) { + case G_IO_STATUS_NORMAL: + case G_IO_STATUS_AGAIN: + return true; + + case G_IO_STATUS_EOF: + /* client has disconnected */ + + httpd_client_close(client); + return false; + + case G_IO_STATUS_ERROR: + /* I/O error */ + + g_warning("failed to write to client: %s", error->message); + g_error_free(error); + + httpd_client_close(client); + return false; + } + + /* unreachable */ + httpd_client_close(client); + return false; +} + +/** + * Data has been received from the client and it is appended to the + * input buffer. + */ +static bool +httpd_client_received(struct httpd_client *client) +{ + char *line; + bool success; + + while ((line = httpd_client_read_line(client)) != NULL) { + success = httpd_client_handle_line(client, line); + g_free(line); + if (!success) + return false; + + if (client->state == RESPONSE) { + if (!fifo_buffer_is_empty(client->input)) { + g_warning("unexpected input from client"); + return false; + } + + fifo_buffer_free(client->input); + + return httpd_client_send_response(client); + } + } + + return true; +} + +static bool +httpd_client_read(struct httpd_client *client) +{ + char *p; + size_t max_length; + GError *error = NULL; + GIOStatus status; + gsize bytes_read; + + if (client->state == RESPONSE) { + /* the client has already sent the request, and he + must not send more */ + g_warning("unexpected input from client"); + return false; + } + + p = fifo_buffer_write(client->input, &max_length); + if (p == NULL) { + g_warning("buffer overflow"); + return false; + } + + status = g_io_channel_read_chars(client->channel, p, max_length, + &bytes_read, &error); + switch (status) { + case G_IO_STATUS_NORMAL: + fifo_buffer_append(client->input, bytes_read); + return httpd_client_received(client); + + case G_IO_STATUS_AGAIN: + /* try again later, after select() */ + return true; + + case G_IO_STATUS_EOF: + /* peer disconnected */ + return false; + + case G_IO_STATUS_ERROR: + /* I/O error */ + g_warning("failed to read from client: %s", + error->message); + g_error_free(error); + return false; + } + + /* unreachable */ + return false; +} + +static gboolean +httpd_client_in_event(G_GNUC_UNUSED GIOChannel *source, GIOCondition condition, + gpointer data) +{ + struct httpd_client *client = data; + struct httpd_output *httpd = client->httpd; + bool ret; + + g_mutex_lock(httpd->mutex); + + if (condition == G_IO_IN && httpd_client_read(client)) { + ret = true; + } else { + httpd_client_close(client); + ret = false; + } + + g_mutex_unlock(httpd->mutex); + + return ret; +} + +struct httpd_client * +httpd_client_new(struct httpd_output *httpd, int fd) +{ + struct httpd_client *client = g_new(struct httpd_client, 1); + + client->httpd = httpd; + +#ifndef G_OS_WIN32 + client->channel = g_io_channel_unix_new(fd); +#else + client->channel = g_io_channel_win32_new_socket(fd); +#endif + + /* GLib is responsible for closing the file descriptor */ + g_io_channel_set_close_on_unref(client->channel, true); + /* NULL encoding means the stream is binary safe */ + g_io_channel_set_encoding(client->channel, NULL, NULL); + /* we prefer to do buffering */ + g_io_channel_set_buffered(client->channel, false); + + client->read_source_id = g_io_add_watch(client->channel, + G_IO_IN|G_IO_ERR|G_IO_HUP, + httpd_client_in_event, client); + + client->input = fifo_buffer_new(4096); + client->state = REQUEST; + + return client; +} + +static void +httpd_client_add_page_size(gpointer data, gpointer user_data) +{ + struct page *page = data; + size_t *size = user_data; + + *size += page->size; +} + +size_t +httpd_client_queue_size(const struct httpd_client *client) +{ + size_t size = 0; + + if (client->state != RESPONSE) + return 0; + + g_queue_foreach(client->pages, httpd_client_add_page_size, &size); + return size; +} + +void +httpd_client_cancel(const struct httpd_client *client) +{ + if (client->state != RESPONSE) + return; + + g_queue_foreach(client->pages, httpd_client_unref_page, NULL); +} + +static GIOStatus +write_page_to_channel(GIOChannel *channel, + const struct page *page, size_t position, + gsize *bytes_written_r, GError **error) +{ + assert(channel != NULL); + assert(page != NULL); + assert(position < page->size); + + return g_io_channel_write_chars(channel, + (const gchar*)page->data + position, + page->size - position, + bytes_written_r, error); +} + +static gboolean +httpd_client_out_event(GIOChannel *source, + G_GNUC_UNUSED GIOCondition condition, gpointer data) +{ + struct httpd_client *client = data; + struct httpd_output *httpd = client->httpd; + GError *error = NULL; + GIOStatus status; + gsize bytes_written; + + g_mutex_lock(httpd->mutex); + + assert(condition == G_IO_OUT); + assert(client->state == RESPONSE); + + if (client->current_page == NULL) { + client->current_page = g_queue_pop_head(client->pages); + client->current_position = 0; + } + + status = write_page_to_channel(source, client->current_page, + client->current_position, + &bytes_written, &error); + switch (status) { + case G_IO_STATUS_NORMAL: + client->current_position += bytes_written; + assert(client->current_position <= client->current_page->size); + + if (client->current_position >= client->current_page->size) { + page_unref(client->current_page); + client->current_page = NULL; + + if (g_queue_is_empty(client->pages)) { + /* all pages are sent: remove the + event source */ + client->write_source_id = 0; + + g_mutex_unlock(httpd->mutex); + return false; + } + } + + g_mutex_unlock(httpd->mutex); + return true; + + case G_IO_STATUS_AGAIN: + g_mutex_unlock(httpd->mutex); + return true; + + case G_IO_STATUS_EOF: + /* client has disconnected */ + + httpd_client_close(client); + g_mutex_unlock(httpd->mutex); + return false; + + case G_IO_STATUS_ERROR: + /* I/O error */ + + g_warning("failed to write to client: %s", error->message); + g_error_free(error); + + httpd_client_close(client); + g_mutex_unlock(httpd->mutex); + return false; + } + + /* unreachable */ + httpd_client_close(client); + g_mutex_unlock(httpd->mutex); + return false; +} + +void +httpd_client_send(struct httpd_client *client, struct page *page) +{ + if (client->state != RESPONSE) + /* the client is still writing the HTTP request */ + return; + + page_ref(page); + g_queue_push_tail(client->pages, page); + + if (client->write_source_id == 0) + client->write_source_id = + g_io_add_watch(client->channel, G_IO_OUT, + httpd_client_out_event, client); +} |