Read default URLs from installed config files

Instead of hardcoding the default version URL and content URL in the
binary, read the defaults from config files that live in
/usr/share/defaults/swupd/.

If the config files do not exist, then users can pass the -c or -v
options as necessary (or -u, which sets the same value for -c and -v).

The primary motivation for this change is to enable a better experience
for the swupd mixer; users mixing a version of Clear Linux can set the
default URLs at mix time instead of always passing -c/-v/-u at runtime.

Signed-off-by: Patrick McCarty <patrick.mccarty@intel.com>

include/swupd.h

@@ -124,11 +124,11 @@ extern void *tm_dlhandle;
 extern char *bundle_to_add;
 extern struct timeval start_time;
 
-extern char *version_server_urls[];
-extern char *preferred_version_url;
-extern char *content_server_urls[];
-extern char *preferred_content_url;
+extern char *version_url;
+extern char *content_url;
 extern long update_server_port;
+extern void set_content_url(char *url);
+extern void set_version_url(char *url);
 
 extern void check_root(void);
 extern void clean_curl_multi_queue(void);

src/check_update.c

@@ -72,10 +72,7 @@ static bool parse_options(int argc, char **argv)
 				goto err;
 			}
 			set_local_download(optarg);
-			if (version_server_urls[0]) {
-				free(version_server_urls[0]);
-			}
-			string_or_die(&version_server_urls[0], "%s", optarg);
+			set_version_url(optarg);
 			break;
 		case 'P':
 			if (sscanf(optarg, "%ld", &update_server_port) != 1) {

src/clr_bundle_add.c

@@ -82,14 +82,8 @@ static bool parse_options(int argc, char **argv)
 				goto err;
 			}
 			set_local_download(optarg);
-			if (version_server_urls[0]) {
-				free(version_server_urls[0]);
-			}
-			if (content_server_urls[0]) {
-				free(content_server_urls[0]);
-			}
-			string_or_die(&version_server_urls[0], "%s", optarg);
-			string_or_die(&content_server_urls[0], "%s", optarg);
+			set_version_url(optarg);
+			set_content_url(optarg);
 			break;
 		case 'p': /* default empty path_prefix verifies the running OS */
 			if (!optarg) {

src/clr_bundle_rm.c

@@ -86,14 +86,8 @@ static bool parse_options(int argc, char **argv)
 				goto err;
 			}
 			set_local_download(optarg);
-			if (version_server_urls[0]) {
-				free(version_server_urls[0]);
-			}
-			if (content_server_urls[0]) {
-				free(content_server_urls[0]);
-			}
-			string_or_die(&version_server_urls[0], "%s", optarg);
-			string_or_die(&content_server_urls[0], "%s", optarg);
+			set_version_url(optarg);
+			set_content_url(optarg);
 			break;
 		case 'P':
 			if (sscanf(optarg, "%ld", &update_server_port) != 1) {

src/curl.c

@@ -426,7 +426,7 @@ CURLcode swupd_curl_set_basic_options(CURL *curl, const char *url)
 		}
 	}
 
-	if (strncmp(url, content_server_urls[1], strlen(content_server_urls[1])) == 0) {
+	if (strncmp(url, content_url, strlen(content_url)) == 0) {
 #warning "SECURITY HOLE since we can't SSL pin arbitrary servers"
 		curl_ret = swupd_curl_set_security_opts(curl);
 		if (curl_ret != CURLE_OK) {

src/download.c

@@ -479,7 +479,7 @@ void full_download(struct file *file)
 		goto out_bad;
 	}
 
-	string_or_die(&url, "%s/%i/files/%s.tar", preferred_content_url, file->last_change, file->hash);
+	string_or_die(&url, "%s/%i/files/%s.tar", content_url, file->last_change, file->hash);
 
 	string_or_die(&filename, "%s/download/.%s.tar", STATE_DIR, file->hash);
 	file->staging = filename;

src/globals.c

@@ -60,20 +60,95 @@ bool download_only;
 bool local_download = false;
 bool have_manifest_diskspace = false; /* assume no until checked */
 bool have_network = false;	    /* assume no access until proved */
-#define URL_COUNT 2
-char *version_server_urls[URL_COUNT] = {
-	NULL,
-	"https://download.clearlinux.org/update",
-};
-char *content_server_urls[URL_COUNT] = {
-	NULL,
-	"https://download.clearlinux.org/update",
-};
-char *preferred_version_url;
-char *preferred_content_url;
+char *version_url = NULL;
+char *content_url = NULL;
 long update_server_port = -1;
 
 #define SWUPD_DEFAULT_FORMAT "3"
+static const char *default_version_url_path = "/usr/share/defaults/swupd/versionurl";
+static const char *default_content_url_path = "/usr/share/defaults/swupd/contenturl";
+
+static int set_default_value(char **global, const char *path)
+{
+	char line[LINE_MAX];
+	FILE *file;
+	char *c;
+
+	file = fopen(path, "r");
+	if (!file) {
+		printf("Error: Unable to open %s\n", path);
+		return -1;
+	}
+
+	/* the file should contain exactly one line */
+	line[0] = 0;
+	if (fgets(line, LINE_MAX, file) == NULL) {
+		if (ferror(file)) {
+			printf("Error: Unable to read data from %s\n", path);
+			return -1;
+		}
+		if (feof(file)) {
+			printf("Error: Contents of %s are empty\n", path);
+			return -1;
+		}
+	}
+
+	/* remove newline if present */
+	c = strchr(line, '\n');
+	if (c) {
+		*c = '\0';
+	}
+
+	string_or_die(global, "%s", line);
+
+	return 0;
+}
+
+static int set_url(char **global, char *url, const char *path)
+{
+	int ret = 0;
+
+	if (url) {
+		if (*global) {
+			free(*global);
+		}
+		string_or_die(global, "%s", url);
+	} else {
+		if (*global) {
+			/* option passed on command line previously */
+			return ret;
+		} else {
+			/* no option passed; use the default value */
+			ret = set_default_value(global, path);
+			if (ret < 0) {
+				return ret;
+			}
+		}
+	}
+
+	return ret;
+}
+
+void set_content_url(char *url) {
+	int ret;
+
+	ret = set_url(&content_url, url, default_content_url_path);
+	if (ret < 0) {
+		printf("\nDefault content URL cannot be read. Use the -c option instead.\n");
+		exit(EXIT_FAILURE);
+	}
+}
+
+void set_version_url(char *url) {
+	int ret;
+
+	ret = set_url(&version_url, url, default_version_url_path);
+	if (ret < 0) {
+		printf("\nDefault version URL cannot be read. Use the -v option instead.\n");
+		exit(EXIT_FAILURE);
+	}
+}
+
 bool set_format_string(char *userinput)
 {
 	int version;
@@ -116,17 +191,8 @@ bool init_globals(void)
 
 	gettimeofday(&start_time, NULL);
 
-	/* pick urls simply from user specified or default */
-	if (version_server_urls[0] != NULL) {
-		preferred_version_url = version_server_urls[0];
-	} else {
-		preferred_version_url = version_server_urls[1];
-	}
-	if (content_server_urls[0] != NULL) {
-		preferred_content_url = content_server_urls[0];
-	} else {
-		preferred_content_url = content_server_urls[1];
-	}
+	set_version_url(NULL);
+	set_content_url(NULL);
 
 	/* insure path_prefix is absolute, at least '/', ends in '/',
 	 * and is a valid dir */
@@ -170,8 +236,8 @@ bool init_globals(void)
 
 void free_globals(void)
 {
-	free(content_server_urls[0]);
-	free(version_server_urls[0]);
+	free(content_url);
+	free(version_url);
 	free(path_prefix);
 	free(format_string);
 	free(mounted_dirs);

src/helpers.c

@@ -749,7 +749,7 @@ int verify_fix_path(char *targetpath, struct manifest *target_MoM)
 		// clean up in case any prior download failed in a partial state
 		unlink(tar_dotfile);
 
-		string_or_die(&url, "%s/%i/files/%s.tar", preferred_content_url, file->last_change, file->hash);
+		string_or_die(&url, "%s/%i/files/%s.tar", content_url, file->last_change, file->hash);
 		ret = swupd_curl_get_file(url, tar_dotfile, NULL, NULL, false);
 
 		if (ret != 0) {

src/main.c

@@ -92,14 +92,8 @@ static bool parse_options(int argc, char **argv)
 				goto err;
 			}
 			set_local_download(optarg);
-			if (version_server_urls[0]) {
-				free(version_server_urls[0]);
-			}
-			if (content_server_urls[0]) {
-				free(content_server_urls[0]);
-			}
-			string_or_die(&version_server_urls[0], "%s", optarg);
-			string_or_die(&content_server_urls[0], "%s", optarg);
+			set_version_url(optarg);
+			set_content_url(optarg);
 			break;
 		case 'P':
 			if (sscanf(optarg, "%ld", &update_server_port) != 1) {
@@ -112,20 +106,14 @@ static bool parse_options(int argc, char **argv)
 				printf("Invalid --contenturl argument\n\n");
 				goto err;
 			}
-			if (content_server_urls[0]) {
-				free(content_server_urls[0]);
-			}
-			string_or_die(&content_server_urls[0], "%s", optarg);
+			set_content_url(optarg);
 			break;
 		case 'v':
 			if (!optarg) {
 				printf("Invalid --versionurl argument\n\n");
 				goto err;
 			}
-			if (version_server_urls[0]) {
-				free(version_server_urls[0]);
-			}
-			string_or_die(&version_server_urls[0], "%s", optarg);
+			set_version_url(optarg);
 			break;
 		case 's':
 			cmd_line_status = true;

src/manifest.c

@@ -437,7 +437,7 @@ static int try_delta_manifest_download(int current, int new, char *component, st
 	memset(&buf, 0, sizeof(struct stat));
 	ret = stat(deltafile, &buf);
 	if (ret || buf.st_size == 0) {
-		string_or_die(&url, "%s/%i/Manifest-%s-delta-from-%i", preferred_content_url, new, component, current);
+		string_or_die(&url, "%s/%i/Manifest-%s-delta-from-%i", content_url, new, component, current);
 
 		ret = swupd_curl_get_file(url, deltafile, NULL, NULL, false);
 		if (ret != 0) {
@@ -509,7 +509,7 @@ static int retrieve_manifests(int current, int version, char *component, struct
 
 	string_or_die(&filename, "%s/%i/Manifest.%s.tar", STATE_DIR, version, component);
 
-	string_or_die(&url, "%s/%i/Manifest.%s.tar", preferred_content_url, version, component);
+	string_or_die(&url, "%s/%i/Manifest.%s.tar", content_url, version, component);
 
 	ret = swupd_curl_get_file(url, filename, NULL, NULL, false);
 	if (ret) {

src/packs.c

@@ -54,7 +54,7 @@ static int download_pack(int oldversion, int newversion, char *module)
 
 	printf("Downloading %s pack for version %i\n", module, newversion);
 
-	string_or_die(&url, "%s/%i/pack-%s-from-%i.tar", preferred_content_url, newversion, module, oldversion);
+	string_or_die(&url, "%s/%i/pack-%s-from-%i.tar", content_url, newversion, module, oldversion);
 
 	err = swupd_curl_get_file(url, filename, NULL, NULL, true);
 	if (err) {

src/search.c

@@ -106,15 +106,8 @@ static bool parse_options(int argc, char **argv)
 				goto err;
 			}
 			set_local_download(optarg);
-			if (version_server_urls[0]) {
-				free(version_server_urls[0]);
-			}
-			if (content_server_urls[0]) {
-				free(content_server_urls[0]);
-			}
-			string_or_die(&version_server_urls[0], "%s", optarg);
-			string_or_die(&content_server_urls[0], "%s", optarg);
-
+			set_version_url(optarg);
+			set_content_url(optarg);
 			break;
 		case 'P':
 			if (sscanf(optarg, "%ld", &update_server_port) != 1) {
@@ -356,7 +349,7 @@ static double query_total_download_size(struct list *list)
 
 		if (access(untard_file, F_OK) == -1) {
 			/* Does not exist client-side. Must download */
-			string_or_die(&url, "%s/%i/Manifest.%s.tar", preferred_content_url,
+			string_or_die(&url, "%s/%i/Manifest.%s.tar", content_url,
 				      file->last_change, file->filename);
 
 			ret = swupd_query_url_content_size(url);
@@ -436,7 +429,7 @@ int download_manifests(struct manifest **MoM)
 		}
 
 		if (access(untard_file, F_OK) == -1) {
-			string_or_die(&url, "%s/%i/Manifest.%s.tar", preferred_content_url, current_version,
+			string_or_die(&url, "%s/%i/Manifest.%s.tar", content_url, current_version,
 				      file->filename);
 
 			printf("Error: Failure reading from %s\n", url);

src/verify.c

@@ -126,14 +126,8 @@ static bool parse_options(int argc, char **argv)
 				goto err;
 			}
 			set_local_download(optarg);
-			if (version_server_urls[0]) {
-				free(version_server_urls[0]);
-			}
-			if (content_server_urls[0]) {
-				free(content_server_urls[0]);
-			}
-			string_or_die(&version_server_urls[0], "%s", optarg);
-			string_or_die(&content_server_urls[0], "%s", optarg);
+			set_version_url(optarg);
+			set_content_url(optarg);
 			break;
 		case 'P':
 			if (sscanf(optarg, "%ld", &update_server_port) != 1) {
@@ -146,20 +140,14 @@ static bool parse_options(int argc, char **argv)
 				printf("Invalid --contenturl argument\n\n");
 				goto err;
 			}
-			if (content_server_urls[0]) {
-				free(content_server_urls[0]);
-			}
-			string_or_die(&content_server_urls[0], "%s", optarg);
+			set_content_url(optarg);
 			break;
 		case 'v':
 			if (!optarg) {
 				printf("Invalid --versionurl argument\n\n");
 				goto err;
 			}
-			if (version_server_urls[0]) {
-				free(version_server_urls[0]);
-			}
-			string_or_die(&version_server_urls[0], "%s", optarg);
+			set_version_url(optarg);
 			break;
 		case 'f':
 			cmdline_option_fix = true;

src/version.c

@@ -46,7 +46,7 @@ static int try_version_download(void)
 		abort();
 	}
 
-	string_or_die(&url, "%s/version/format%s/latest", preferred_version_url, format_string);
+	string_or_die(&url, "%s/version/format%s/latest", version_url, format_string);
 
 	string_or_die(&path, "%s/server_version", STATE_DIR);