diff options
| -rw-r--r-- | gatchat/gatserver.c | 266 |
1 files changed, 165 insertions, 101 deletions
diff --git a/gatchat/gatserver.c b/gatchat/gatserver.c index dd481944..a1f23983 100644 --- a/gatchat/gatserver.c +++ b/gatchat/gatserver.c @@ -32,6 +32,22 @@ #include "ringbuffer.h" #include "gatserver.h" +enum ParserState { + PARSER_STATE_IDLE, + PARSER_STATE_A, + PARSER_STATE_SLASH, + PARSER_STATE_COMMAND, + PARSER_STATE_GARBAGE, +}; + +enum ParserResult { + PARSER_RESULT_COMMAND, + PARSER_RESULT_EMPTY_COMMAND, + PARSER_RESULT_REPEAT_LAST, + PARSER_RESULT_GARBAGE, + PARSER_RESULT_UNSURE, +}; + /* V.250 Table 1/V.250 Result codes */ static const char *server_result_to_string(GAtServerResult result) { @@ -82,10 +98,9 @@ struct _GAtServer { gpointer debug_data; /* Data to pass to debug func */ struct ring_buffer *buf; /* Current read buffer */ guint max_read_attempts; /* Max reads per select */ + enum ParserState parser_state; }; -static int at_server_parse(GAtServer *server, char *buf); - static void g_at_server_send_result(GAtServer *server, GAtServerResult result) { struct v250_settings v250 = server->v250; @@ -113,111 +128,155 @@ static void g_at_server_send_result(GAtServer *server, GAtServerResult result) &wbuf); } -static gsize skip_space(const char *buf, gsize pos) -{ - gsize i = pos; - char c = buf[i]; - - while (c == ' ') - c = buf[++i]; - - return i; -} - static inline gboolean is_at_command_prefix(const char c) { - if (c == '&') + switch (c) { + case '+': + case '*': + case '!': + case '%': + return TRUE; + default: return FALSE; - - return g_ascii_ispunct(c); + } } -static int parse_at_command(GAtServer *server, char *buf) +static void parse_at_command(GAtServer *server, char *buf) { - int res = G_AT_SERVER_RESULT_ERROR; - - return res; + g_at_server_send_result(server, G_AT_SERVER_RESULT_ERROR); } -static int parse_v250_settings(GAtServer *server, char *buf) +static void parse_v250_settings(GAtServer *server, char *buf) { - int res = G_AT_SERVER_RESULT_ERROR; - - return res; + g_at_server_send_result(server, G_AT_SERVER_RESULT_ERROR); } -static int at_server_parse(GAtServer *server, char *buf) +static void server_parse_line(GAtServer *server, char *line) { - int res = G_AT_SERVER_RESULT_ERROR; gsize i = 0; char c; - /* skip space after "AT" or previous command */ - i = skip_space(buf, i); + if (line == NULL) { + g_at_server_send_result(server, G_AT_SERVER_RESULT_ERROR); + goto done; + } + + if (line[0] == '\0') { + g_at_server_send_result(server, G_AT_SERVER_RESULT_OK); + goto done; + } - c = buf[i]; + c = line[i]; /* skip semicolon */ if (c == ';') - c = buf[++i]; + c = line[++i]; if (is_at_command_prefix(c) || c == 'A' || c == 'D' || c == 'H') - res = parse_at_command(server, buf + i); + parse_at_command(server, line + i); else if (g_ascii_isalpha(c) || c == '&') - res = parse_v250_settings(server, buf + i); - else if (c == '\0') - res = G_AT_SERVER_RESULT_OK; + parse_v250_settings(server, line + i); + else + g_at_server_send_result(server, G_AT_SERVER_RESULT_ERROR); - return res; +done: + g_free(line); } -static void parse_buffer(GAtServer *server, char *buf) +static enum ParserResult server_feed(GAtServer *server, + const char *bytes, gsize *len) { - int res = G_AT_SERVER_RESULT_ERROR; gsize i = 0; + enum ParserResult res = PARSER_RESULT_UNSURE; + char s3 = server->v250.s3; + + while (i < *len) { + char byte = bytes[i]; + + switch (server->parser_state) { + case PARSER_STATE_IDLE: + if (byte == s3) { + i += 1; + res = PARSER_RESULT_EMPTY_COMMAND; + goto out; + } else if (byte == '\n') { + i += 1; + res = PARSER_RESULT_GARBAGE; + goto out; + } else if (byte == 'A' || byte == 'a') + server->parser_state = PARSER_STATE_A; + else if (byte != ' ' && byte != '\t') + server->parser_state = PARSER_STATE_GARBAGE; + break; - if (!buf) - return; + case PARSER_STATE_A: + if (byte == s3) { + server->parser_state = PARSER_STATE_IDLE; + i += 1; + res = PARSER_RESULT_GARBAGE; + goto out; + } else if (byte == '/') + server->parser_state = PARSER_STATE_SLASH; + else if (byte == 'T' || byte == 't') + server->parser_state = PARSER_STATE_COMMAND; + else + server->parser_state = PARSER_STATE_GARBAGE; - g_at_util_debug_chat(TRUE, (char *) buf, strlen(buf), - server->debugf, server->debug_data); + break; - /* skip header space */ - buf += skip_space(buf, i); + case PARSER_STATE_SLASH: + if (byte == s3) { + server->parser_state = PARSER_STATE_IDLE; + i+= 1; + res = PARSER_RESULT_REPEAT_LAST; + goto out; + } else if (byte != ' ' && byte != '\t') + server->parser_state = PARSER_STATE_GARBAGE; - /* Make sure the command line prefix is "AT" or "at" */ - if (g_str_has_prefix(buf, "AT") || - g_str_has_prefix(buf, "at")) - res = at_server_parse(server, (char *) buf + 2); + break; - g_at_server_send_result(server, res); + case PARSER_STATE_COMMAND: + if (byte == s3) { + server->parser_state = PARSER_STATE_IDLE; + i += 1; + res = PARSER_RESULT_COMMAND; + goto out; + } + break; - /* We're overflowing the buffer, shutdown the socket */ - if (server->buf && ring_buffer_avail(server->buf) == 0) - g_at_server_shutdown(server); + case PARSER_STATE_GARBAGE: + if (byte == s3) { + server->parser_state = PARSER_STATE_IDLE; + + i += 1; + res = PARSER_RESULT_GARBAGE; + goto out; + } + break; + + default: + break; + }; - if (buf) - g_free(buf); + i += 1; + } + +out: + *len = i; + return res; } -static char *extract_line(GAtServer *p, unsigned int *unread) +static char *extract_line(GAtServer *p) { unsigned int wrap = ring_buffer_len_no_wrap(p->buf); unsigned int pos = 0; unsigned char *buf = ring_buffer_read_ptr(p->buf, pos); - char s3 = p->v250.s3; - char s4 = p->v250.s4; - char *line; - int strip_front = 0; - int strip_tail = 0; int line_length = 0; + char *line; while (pos < p->read_so_far) { - if (*buf == s3 || *buf == s4) - if (!line_length) + if (line_length == 0 && (*buf == ' ' || *buf == '\t')) strip_front += 1; - else - break; else line_length += 1; @@ -228,10 +287,8 @@ static char *extract_line(GAtServer *p, unsigned int *unread) buf = ring_buffer_read_ptr(p->buf, pos); } - if (!line_length) { - ring_buffer_drain(p->buf, strip_front); - return NULL; - } + /* We will strip AT and \r */ + line_length -= 3; line = g_try_new(char, line_length + 1); @@ -240,28 +297,14 @@ static char *extract_line(GAtServer *p, unsigned int *unread) return NULL; } - ring_buffer_drain(p->buf, strip_front); + /* Strip leading whitespace + AT */ + ring_buffer_drain(p->buf, strip_front + 2); ring_buffer_read(p->buf, line, line_length); + /* Strip \r */ + ring_buffer_drain(p->buf, 1); line[line_length] = '\0'; - while (pos < p->read_so_far) { - if (*buf == s3 || *buf == s4) - strip_tail += 1; - else - break; - - buf += 1; - pos += 1; - - if (pos == wrap) - buf = ring_buffer_read_ptr(p->buf, pos); - } - - ring_buffer_drain(p->buf, strip_tail); - - *unread = p->read_so_far - strip_front - line_length - strip_tail; - return line; } @@ -270,35 +313,56 @@ static void new_bytes(GAtServer *p) unsigned int len = ring_buffer_len(p->buf); unsigned int wrap = ring_buffer_len_no_wrap(p->buf); unsigned char *buf = ring_buffer_read_ptr(p->buf, p->read_so_far); - char s3 = p->v250.s3; + enum ParserState result; - while (p->read_so_far < len) { + while (p->server_io && (p->read_so_far < len)) { gsize rbytes = MIN(len - p->read_so_far, wrap - p->read_so_far); - unsigned char *s3_pos = memchr(buf, s3, rbytes); - char *line = NULL; - unsigned int unread = 0; + result = server_feed(p, (char *)buf, &rbytes); + buf += rbytes; p->read_so_far += rbytes; - if (s3_pos) - line = extract_line(p, &unread); - - buf += rbytes - unread; - p->read_so_far -= unread; - if (p->read_so_far == wrap) { buf = ring_buffer_read_ptr(p->buf, p->read_so_far); wrap = len; } - if (s3_pos) { - parse_buffer(p, line); + if (result == PARSER_RESULT_UNSURE) + continue; + + switch (result) { + case PARSER_RESULT_EMPTY_COMMAND: + /* + * According to section 5.2.4 and 5.6 of V250, + * Empty commands must be OK by the DCE + */ + g_at_server_send_result(p, G_AT_SERVER_RESULT_OK); + ring_buffer_drain(p->buf, p->read_so_far); + break; + + case PARSER_RESULT_COMMAND: + server_parse_line(p, extract_line(p)); + break; + + case PARSER_RESULT_REPEAT_LAST: + /* TODO */ + g_at_server_send_result(p, G_AT_SERVER_RESULT_OK); + ring_buffer_drain(p->buf, p->read_so_far); + break; - len -= p->read_so_far; - wrap -= p->read_so_far; - p->read_so_far = 0; + default: + ring_buffer_drain(p->buf, p->read_so_far); + break; } + + len -= p->read_so_far; + wrap -= p->read_so_far; + p->read_so_far = 0; } + + /* We're overflowing the buffer, shutdown the socket */ + if (p->buf && ring_buffer_avail(p->buf) == 0) + g_source_remove(p->server_watch); } static gboolean received_data(GIOChannel *channel, GIOCondition cond, |