Map Fetch Failure

/* * Copyright © 2018 Keith Packard * * 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. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define ALTOS_MAP_PORT 16717 #define MISSING 0x7fffffff #define ALTOS_MAP_PROTOCOL_VERSION "1.0.0" static char * reason_string(int code) { switch (code) { case 200: return "OK"; case 400: return "Bad Request"; case 403: return "Forbidden"; case 404: return "Not Found"; case 408: return "Request Timeout"; default: return "Failure"; } } static void write_status(int status) { printf("Status: %d %s\n", status, reason_string(status)); } static void write_type(char * type) { printf("Content-Type: %s\n", type); } static void fail(int status, char *format, ...) { va_list ap; write_status(status); write_type("text/html"); printf("\n"); printf("\n"); printf("Map Fetch Failure\n"); printf("\n"); va_start(ap, format); vprintf(format, ap); va_end(ap); printf("\n"); printf("\n"); exit(1); } static char * getenv_copy(const char *name) { const char *value = getenv(name); if (!value) return NULL; return strdup(value); } static double parse_double(char *string) { char *end; double value; value = strtod(string, &end); if (*end) fail(400, "Invalid double %s", string); return value; } static int parse_int(char *string) { char *end; long int value; value = strtol(string, &end, 10); if (*end) fail(400, "Invalid int %s", string); if (value < INT_MIN || INT_MAX < value) fail(400, "Int value out of range %ld", value); return (int) value; } static int connect_service(void) { struct sockaddr_in altos_map_addr = { .sin_family = AF_INET, .sin_port = htons(ALTOS_MAP_PORT), .sin_addr = { .s_addr = htonl(INADDR_LOOPBACK), }, }; int s = socket(AF_INET, SOCK_STREAM, 0); if (s < 0) return -1; if (connect (s, (const struct sockaddr *) &altos_map_addr, sizeof (altos_map_addr)) < 0) { close (s); return -1; } return s; } int main(int argc, char **argv) { char *query_string = getenv_copy("QUERY_STRING"); if (query_string == NULL) fail(400, "%s", "Missing query string"); char *remote_addr = getenv_copy("REMOTE_ADDR"); if (remote_addr == NULL) fail(400, "%s", "Missing remote address"); double lon = MISSING; double lat = MISSING; int zoom = MISSING; char *version = NULL; char *query, *query_save = NULL; char *query_start = query_string; while ((query = strtok_r(query_start, "&", &query_save)) != NULL) { query_start = NULL; char *token, *token_save = NULL; char *token_start = query; char *name = NULL; char *value = NULL; while ((token = strtok_r(token_start, "=", &token_save)) != NULL) { token_start = NULL; if (name == NULL) name = token; else if (value == NULL) value = token; else break; } if (name && value) { if (!strcmp(name, "lon")) lon = parse_double(value); else if (!strcmp(name, "lat")) lat = parse_double(value); else if (!strcmp(name, "zoom")) zoom = parse_int(value); else if (!strcmp(name, "version")) version = value; else fail(400, "Extra query param \"%s\"", query); } } if (version != NULL) { printf("Content-Type: text/plain\n"); printf("\n"); printf("%s\n", ALTOS_MAP_PROTOCOL_VERSION); return 0; } if (lon == MISSING) fail(400, "Missing longitude"); if (lat == MISSING) fail(400, "Missing latitude"); if (zoom == MISSING) fail(400, "Missing zoom"); int s = -1; int tries = 0; while (tries < 10 && s < 0) { s = connect_service(); if (s < 0) { usleep(100 * 1000); tries++; } } if (s < 0) fail(408, "Cannot connect AltOS map daemon"); FILE *sf = fdopen(s, "r+"); if (sf == NULL) fail(400, "allocation failure"); json_t *request = json_pack("{s:f s:f s:i s:s}", "lat", lat, "lon", lon, "zoom", zoom, "remote_addr", remote_addr); if (request == NULL) fail(400, "Cannot create JSON request"); if (json_dumpf(request, sf, 0) < 0) fail(400, "Cannot write JSON request"); fflush(sf); json_error_t error; json_t *reply = json_loadf(sf, 0, &error); if (!reply) fail(400, "Cannot read JSON reply"); int status; if (json_unpack(reply, "{s:i}", "status", &status) < 0) fail(400, "No status returned"); if (status != 200) fail(status, "Bad cache status"); char *filename, *content_type; if (json_unpack(reply, "{s:s s:s}", "filename", &filename, "content_type", &content_type) < 0) fail(400, "JSON reply parse failure"); int fd = open(filename, O_RDONLY); if (fd < 0) fail(400, "%s: %s", filename, strerror(errno)); struct stat statb; if (fstat(fd, &statb) < 0) fail(400, "%s: %s", filename, strerror(errno)); printf("Content-Type: %s\n", content_type); printf("Content-Length: %lu\n", (unsigned long) statb.st_size); printf("\n"); fflush(stdout); char buf[4096]; ssize_t bytes_read; while ((bytes_read = read(fd, buf, sizeof (buf))) > 0) { ssize_t total_write = 0; while (total_write < bytes_read) { ssize_t bytes_write = write(1, buf + total_write, bytes_read - total_write); if (bytes_write <= 0) return 1; total_write += bytes_write; } } if (bytes_read < 0) return 1; return 0; }