misc: Replace rc_getline and getline with xgetline.

rc_getline is an implementation from when getline wasn't available on
most libcs, and is planned for removal, however much of of the code
relies on it's behaviour of removing new lines at the end of strings.

To avoid duplicating the new line removal logic in a dozen places, we
introduce a new helper function xgetline, which just wraps around
getline but removes the new line at the end.

src/kill_all/kill_all.c

@@ -115,7 +115,7 @@ static bool is_user_process(pid_t pid)
 		temp_pid = -1;
 		while (!feof(fp)) {
 			buf = NULL;
-			if (getline(&buf, &size, fp) != -1) {
+			if (xgetline(&buf, &size, fp) != -1) {
 				sscanf(buf, "PPid: %d", &temp_pid);
 				free(buf);
 			} else {

src/librc/librc-daemon.c

@@ -140,8 +140,7 @@ rc_find_pids(const char *exec, const char *const *argv, uid_t uid, pid_t pid)
 	if (exists("/proc/self/status")) {
 		fp = fopen("/proc/self/status", "r");
 		if (fp) {
-			while (!feof(fp)) {
-				rc_getline(&line, &len, fp);
+			while (xgetline(&line, &len, fp) != -1) {
 				if (strncmp(line, "envID:\t0", 8) == 0) {
 					openvz_host = true;
 					break;
@@ -196,8 +195,7 @@ rc_find_pids(const char *exec, const char *const *argv, uid_t uid, pid_t pid)
 				free(buffer);
 				if (!fp)
 					continue;
-				while (!feof(fp)) {
-					rc_getline(&line, &len, fp);
+				while (xgetline(&line, &len, fp) != -1) {
 					if (strncmp(line, "envID:", 6) == 0) {
 						container_pid = !(strncmp(line, "envID:\t0", 8) == 0);
 						break;
@@ -346,7 +344,7 @@ _match_daemon(const char *path, const char *file, RC_STRINGLIST *match)
 	if (!fp)
 		return false;
 
-	while ((rc_getline(&line, &len, fp))) {
+	while (xgetline(&line, &len, fp) != -1) {
 		TAILQ_FOREACH(m, match, entries)
 		    if (strcmp(line, m->value) == 0) {
 			    TAILQ_REMOVE(match, m, entries);
@@ -559,7 +557,7 @@ rc_service_daemons_crashed(const char *service)
 		if (!fp)
 			break;
 
-		while ((rc_getline(&line, &len, fp))) {
+		while (xgetline(&line, &len, fp) != -1) {
 			p = line;
 			if ((token = strsep(&p, "=")) == NULL || !p)
 				continue;

src/librc/librc-depend.c

@@ -160,8 +160,7 @@ rc_deptree_load_file(const char *deptree_file)
 	RC_DEPINFO *depinfo = NULL;
 	RC_DEPTYPE *deptype = NULL;
 	char *line = NULL;
-	size_t len = 0;
-	ssize_t size;
+	size_t size;
 	char *type;
 	char *p;
 	char *e;
@@ -171,8 +170,7 @@ rc_deptree_load_file(const char *deptree_file)
 		return NULL;
 
 	deptree = make_deptree();
-	while ((size = getline(&line, &len, fp)) != -1) {
-		line[size - 1] = '\0';
+	while (xgetline(&line, &size, fp) != -1) {
 		p = line;
 		e = strsep(&p, "_");
 		if (!e || strcmp(e, "depinfo") != 0)
@@ -788,8 +786,7 @@ rc_deptree_update(void)
 	RC_STRINGLIST *config, *dupes, *types, *sorted, *visited;
 	RC_STRING *s, *s2, *s2_np, *s3, *s4;
 	char *line = NULL;
-	size_t len = 0;
-	ssize_t size;
+	size_t size;
 	char *depend, *depends, *service, *type;
 	size_t i, l;
 	bool retval = true;
@@ -811,8 +808,7 @@ rc_deptree_update(void)
 	config = rc_stringlist_new();
 
 	deptree = make_deptree();
-	while ((size = getline(&line, &len, fp)) != -1) {
-		line[size - 1] = '\0';
+	while (xgetline(&line, &size, fp) != -1) {
 		depends = line;
 		service = strsep(&depends, " ");
 		if (!service || !*service)
@@ -894,8 +890,8 @@ rc_deptree_update(void)
 	 * work for them. This doesn't stop them from being run directly. */
 	if (sys) {
 		char *nosys, *onosys;
+		size_t len = strlen(sys);
 
-		len = strlen(sys);
 		nosys = xmalloc(len + 2);
 		nosys[0] = '-';
 		for (i = 0; i < len; i++)

src/librc/librc-misc.c

@@ -133,7 +133,6 @@ rc_proc_getent(const char *ent RC_UNUSED)
 	FILE *fp;
 	char *proc = NULL, *p, *value = NULL, *save;
 	size_t i, len;
-	ssize_t size;
 
 	if (!exists("/proc/cmdline"))
 		return NULL;
@@ -142,11 +141,10 @@ rc_proc_getent(const char *ent RC_UNUSED)
 		return NULL;
 
 	i = 0;
-	if ((size = getline(&proc, &i, fp)) == -1) {
+	if (xgetline(&proc, &i, fp) == -1) {
 		free(proc);
 		return NULL;
 	}
-	proc[size - 1] = '\0';
 	save = proc;
 
 	len = strlen(ent);
@@ -184,7 +182,7 @@ rc_config_list(const char *file)
 	if (!(fp = fopen(file, "r")))
 		return list;
 
-	while ((rc_getline(&buffer, &len, fp))) {
+	while (xgetline(&buffer, &len, fp) != -1) {
 		p = buffer;
 		/* Strip leading spaces/tabs */
 		while ((*p == ' ') || (*p == '\t'))

src/librc/librc.c

@@ -175,7 +175,8 @@ file_regex(const char *file, const char *regex)
 {
 	FILE *fp;
 	char *line = NULL;
-	size_t size = 0, len = 0;
+	size_t size = 0;
+	ssize_t len = 0;
 	regex_t re;
 	bool retval = true;
 	int result;
@@ -192,7 +193,7 @@ file_regex(const char *file, const char *regex)
 		return false;
 	}
 
-	while ((len = rc_getline(&line, &size, fp))) {
+	while ((len = xgetline(&line, &size, fp)) != -1) {
 		char *str = line;
 		/* some /proc files have \0 separated content so we have to
 		   loop through the 'line' */
@@ -702,19 +703,22 @@ rc_service_extra_commands(const char *service)
 	snprintf(cmd, l, OPTSTR, svc);
 	free(svc);
 
-	if ((fp = popen(cmd, "r"))) {
-		rc_getline(&buffer, &len, fp);
+	if (!(fp = popen(cmd, "r"))) {
+		free(cmd);
+		return NULL;
+	}
+
+	if (xgetline(&buffer, &len, fp) != -1) {
 		p = buffer;
 		commands = rc_stringlist_new();
 
 		while ((token = strsep(&p, " ")))
 			if (token[0] != '\0')
 				rc_stringlist_add(commands, token);
-
-		pclose(fp);
-		free(buffer);
 	}
 
+	pclose(fp);
+	free(buffer);
 	free(cmd);
 	return commands;
 }
@@ -726,7 +730,7 @@ rc_service_description(const char *service, const char *option)
 	char *svc;
 	char *cmd;
 	char *desc = NULL;
-	size_t len = 0;
+	size_t size = 0;
 	FILE *fp;
 	size_t l;
 
@@ -741,7 +745,10 @@ rc_service_description(const char *service, const char *option)
 	snprintf(cmd, l, DESCSTR, svc, *option ? "_" : "", option);
 	free(svc);
 	if ((fp = popen(cmd, "r"))) {
-		rc_getline(&desc, &len, fp);
+		if (xgetline(&desc, &size, fp) == -1) {
+			free(desc);
+			desc = NULL;
+		}
 		pclose(fp);
 	}
 	free(cmd);

src/mountinfo/mountinfo.c

@@ -327,7 +327,7 @@ find_mounts(struct args *args)
 	list = rc_stringlist_new();
 
 	buffer = NULL;
-	while (getline(&buffer, &size, fp) != -1) {
+	while (xgetline(&buffer, &size, fp) != -1) {
 		netdev = -1;
 		p = buffer;
 		from = strsep(&p, " ");

src/openrc/rc.c

@@ -335,11 +335,11 @@ static char *get_krunlevel(void)
 		return NULL;
 	}
 
-	if (getline(&buffer, &i, fp) != -1) {
-		i = strlen(buffer);
-		if (buffer[i - 1] == '\n')
-			buffer[i - 1] = 0;
+	if (xgetline(&buffer, &i, fp) == -1) {
+		free(buffer);
+		buffer = NULL;
 	}
+
 	fclose(fp);
 	return buffer;
 }

src/shared/helpers.h

@@ -165,4 +165,16 @@ RC_UNUSED RC_PRINTF(2,3) static int xasprintf(char **strp, const char *fmt, ...)
 	return len;
 }
 
+RC_UNUSED static ssize_t xgetline(char **restrict lineptr, size_t *restrict n, FILE *restrict stream)
+{
+	ssize_t ret = getline(lineptr, n, stream);
+	if (ret == -1)
+		return -1;
+
+	if ((*lineptr)[*n - 1] == '\n')
+		(*lineptr)[(*n--) - 1] = '\0';
+
+	return ret;
+}
+
 #endif

src/shared/misc.c

@@ -183,15 +183,12 @@ env_config(void)
 	free(e);
 
 	if ((fp = fopen(RC_KRUNLEVEL, "r"))) {
-		if (getline(&buffer, &size, fp) != -1) {
-			l = strlen (buffer) - 1;
-			if (buffer[l] == '\n')
-				buffer[l] = 0;
+		if (xgetline(&buffer, &size, fp) != -1)
 			setenv("RC_DEFAULTLEVEL", buffer, 1);
-		}
 		fclose(fp);
-	} else
+	} else {
 		setenv("RC_DEFAULTLEVEL", RC_LEVEL_DEFAULT, 1);
+	}
 
 	free(buffer);
 	if (sys)

src/shared/selinux.c

@@ -261,7 +261,6 @@ static int read_context_file(const char *filename, char **context)
 	char *p;
 	char *p2;
 	size_t len = 0;
-	ssize_t read;
 
 	xasprintf(&filepath, "%s/%s", selinux_contexts_path(), filename);
 
@@ -272,7 +271,7 @@ static int read_context_file(const char *filename, char **context)
 		return -1;
 	}
 
-	while ((read = getline(&line, &len, fp)) != -1) {
+	while (xgetline(&line, &len, fp) != -1) {
 		/* cut off spaces before the string */
 		p = line;
 		while (isspace(*p) && *p != '\0')

src/start-stop-daemon/start-stop-daemon.c

@@ -745,7 +745,7 @@ int main(int argc, char **argv)
 		fp = fopen(exec_file, "r");
 		if (fp) {
 			line = NULL;
-			if (getline(&line, &size, fp) == -1)
+			if (xgetline(&line, &size, fp) == -1)
 				eerrorx("%s: %s", applet, strerror(errno));
 			p = line;
 			fclose(fp);
@@ -754,10 +754,6 @@ int main(int argc, char **argv)
 				/* Strip leading spaces */
 				while (*p == ' ' || *p == '\t')
 					p++;
-				/* Remove the trailing newline */
-				len = strlen(p) - 1;
-				if (p[len] == '\n')
-					p[len] = '\0';
 				token = strsep(&p, " ");
 				free(exec_file);
 				xasprintf(&exec_file, "%s", token);