libmount: use const char in fstab parser

The parser does not modify the string, so let's keep it "const char".

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/libmount/src/tab_parse.c b/libmount/src/tab_parse.c
index 4944d5f8c33794897c45e65073878c1014bcaa6a..316aee7f63fb25fc7f7e94f3a022c2426cd14c54 100644 (file)
--- a/libmount/src/tab_parse.c
+++ b/libmount/src/tab_parse.c
@@ -39,32 +39,34 @@ static void parser_cleanup(struct libmnt_parser *pa)
        memset(pa, 0, sizeof(*pa));
 }
 
-static int next_number(char **s, int *num)
+static const char *next_number(const char *s, int *num, int *ok)
 {
        char *end = NULL;
 
        assert(num);
        assert(s);
+       assert(ok);
 
-       *s = (char *) skip_blank(*s);
-       if (!**s)
-               return -1;
-       *num = strtol(*s, &end, 10);
-       if (end == NULL || *s == end)
-              return -1;
+       *ok = 0;
+       s = skip_blank(s);
+       if (!s || !*s)
+               return s;
 
-       *s = end;
+       *num = strtol(s, &end, 10);
+       if (end == NULL || s == end)
+              return s;
 
        /* valid end of number is a space or a terminator */
        if (*end == ' ' || *end == '\t' || *end == '\0')
-               return 0;
-       return -1;
+               *ok = 1;
+
+       return end;
 }
 
 /*
  * Parses one line from {fs,m}tab
  */
-static int mnt_parse_table_line(struct libmnt_fs *fs, char *s)
+static int mnt_parse_table_line(struct libmnt_fs *fs, const char *s)
 {
        int rc, n = 0, xrc;
        char *src = NULL, *fstype = NULL, *optstr = NULL;
@@ -119,16 +121,22 @@ static int mnt_parse_table_line(struct libmnt_fs *fs, char *s)
        fs->passno = fs->freq = 0;
 
        if (xrc == 4 && n)
-               s = (char *) skip_blank(s + n);
+               s = skip_blank(s + n);
        if (xrc == 4 && *s) {
-               if (next_number(&s, &fs->freq) != 0) {
-                       if (*s) {
+               int ok = 0;
+
+               s = next_number(s, &fs->freq, &ok);
+               if (!ok) {
+                       if (s && *s) {
                                DBG(TAB, ul_debug("tab parse error: [freq]"));
                                rc = -EINVAL;
                        }
-               } else if (next_number(&s, &fs->passno) != 0 && *s) {
-                       DBG(TAB, ul_debug("tab parse error: [passno]"));
-                       rc = -EINVAL;
+               } else {
+                       s = next_number(s, &fs->passno, &ok);
+                       if (!ok && s && *s) {
+                               DBG(TAB, ul_debug("tab parse error: [passno]"));
+                               rc = -EINVAL;
+                       }
                }
        }
 
@@ -389,9 +397,9 @@ static int guess_table_format(char *line)
        return MNT_FMT_FSTAB;           /* fstab, mtab or /proc/mounts */
 }
 
-static int is_comment_line(char *line)
+static int is_comment_line(const char *line)
 {
-       char *p = (char *) skip_blank(line);
+       const char *p = skip_blank(line);
 
        if (p && (*p == '#' || *p == '\n'))
                return 1;