utils: make detect_ramfs_rootfs() return bool

src/lxc/utils.c

@@ -1158,36 +1158,40 @@ bool switch_to_ns(pid_t pid, const char *ns) {
  * IIUC, so long as we've chrooted so that rootfs is not our root,
  * the rootfs entry should always be skipped in mountinfo contents.
  */
-int detect_ramfs_rootfs(void)
+bool detect_ramfs_rootfs(void)
 {
-	char buf[LINELEN], *p;
 	FILE *f;
+	char *p, *p2;
+	char *line = NULL;
+	size_t len = 0;
 	int i;
-	char *p2;
 
 	f = fopen("/proc/self/mountinfo", "r");
 	if (!f)
-		return 0;
-	while (fgets(buf, LINELEN, f)) {
-		for (p = buf, i=0; p && i < 4; i++)
-			p = strchr(p+1, ' ');
+		return false;
+
+	while (getline(&line, &len, f) != -1) {
+		for (p = line, i = 0; p && i < 4; i++)
+			p = strchr(p + 1, ' ');
 		if (!p)
 			continue;
-		p2 = strchr(p+1, ' ');
+		p2 = strchr(p + 1, ' ');
 		if (!p2)
 			continue;
 		*p2 = '\0';
-		if (strcmp(p+1, "/") == 0) {
+		if (strcmp(p + 1, "/") == 0) {
 			// this is '/'.  is it the ramfs?
-			p = strchr(p2+1, '-');
+			p = strchr(p2 + 1, '-');
 			if (p && strncmp(p, "- rootfs rootfs ", 16) == 0) {
+				free(line);
 				fclose(f);
-				return 1;
+				return true;
 			}
 		}
 	}
+	free(line);
 	fclose(f);
-	return 0;
+	return false;
 }
 
 char *on_path(char *cmd, const char *rootfs) {

src/lxc/utils.h

@@ -293,7 +293,7 @@ extern bool dir_exists(const char *path);
 uint64_t fnv_64a_buf(void *buf, size_t len, uint64_t hval);
 
 int detect_shared_rootfs(void);
-int detect_ramfs_rootfs(void);
+bool detect_ramfs_rootfs(void);
 char *on_path(char *cmd, const char *rootfs);
 bool file_exists(const char *f);
 bool cgns_supported(void);