diff options
Diffstat (limited to 'map-server/altos-map/altos-map.c')
| -rw-r--r-- | map-server/altos-map/altos-map.c | 286 |
1 files changed, 286 insertions, 0 deletions
diff --git a/map-server/altos-map/altos-map.c b/map-server/altos-map/altos-map.c new file mode 100644 index 00000000..690ec728 --- /dev/null +++ b/map-server/altos-map/altos-map.c @@ -0,0 +1,286 @@ +/* + * Copyright © 2018 Keith Packard <keithp@keithp.com> + * + * 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 <jansson.h> +#include <stdlib.h> +#include <stdarg.h> +#include <stdint.h> +#include <stdio.h> +#include <unistd.h> +#include <string.h> +#include <fcntl.h> +#include <errno.h> +#include <limits.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/socket.h> +#include <netinet/ip.h> + +#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("<html>\n"); + printf("<head><title>Map Fetch Failure</title></head>\n"); + printf("<body>\n"); + va_start(ap, format); + vprintf(format, ap); + va_end(ap); + printf("</body>\n"); + printf("</html>\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"); + + 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_dumpfd(request, s, 0) < 0) + fail(400, "Cannot write JSON request"); + + json_error_t error; + json_t *reply = json_loadfd(s, 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; +} |