Fix gcc 8.1.1 compiler warnings

    CC ../shared.o
../shared.c: In function ‘expand_macro’:
../shared.c:487:3: warning: ‘strncpy’ specified bound depends on the length of the source argument [-Wstringop-overflow=]
   strncpy(name, value, len);
   ^~~~~~~~~~~~~~~~~~~~~~~~~
../shared.c:484:9: note: length computed here
   len = strlen(value);
         ^~~~~~~~~~~~~
../ui-shared.c: In function ‘cgit_repobasename’:
../ui-shared.c:136:2: warning: ‘strncpy’ specified bound 1024 equals destination size [-Wstringop-truncation]
  strncpy(rvbuf, reponame, sizeof(rvbuf));
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    CC ../ui-ssdiff.o
../ui-ssdiff.c: In function ‘replace_tabs’:
../ui-ssdiff.c:142:4: warning: ‘strncat’ output truncated copying between 1 and 8 bytes from a string of length 8 [-Wstringop-truncation]
    strncat(result, spaces, 8 - (strlen(result) % 8));
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

diff --git a/shared.c b/shared.c
index f7b64cf317ced6a7dd5ce33fce48e74c149c0e5f..609bd2a30670e5eab7974593fd98c6d9e95c24bc 100644 (file)
--- a/shared.c
+++ b/shared.c
@@ -476,15 +476,16 @@ static int is_token_char(char c)
 static char *expand_macro(char *name, int maxlength)
 {
        char *value;
-       int len;
+       size_t len;
 
        len = 0;
        value = getenv(name);
        if (value) {
-               len = strlen(value);
+               len = strlen(value) + 1;
                if (len > maxlength)
                        len = maxlength;
-               strncpy(name, value, len);
+               strlcpy(name, value, len);
+               --len;
        }
        return name + len;
 }

diff --git a/ui-shared.c b/ui-shared.c
index 066a470e5dd419b503bd4ff80646028079f844ad..739505a865cc7660621f28666474ec9c6d624718 100644 (file)
--- a/ui-shared.c
+++ b/ui-shared.c
@@ -133,20 +133,25 @@ const char *cgit_repobasename(const char *reponame)
        static char rvbuf[1024];
        int p;
        const char *rv;
-       strncpy(rvbuf, reponame, sizeof(rvbuf));
-       if (rvbuf[sizeof(rvbuf)-1])
+       size_t len;
+
+       len = strlcpy(rvbuf, reponame, sizeof(rvbuf));
+       if (len >= sizeof(rvbuf))
                die("cgit_repobasename: truncated repository name '%s'", reponame);
-       p = strlen(rvbuf)-1;
+       p = len - 1;
        /* strip trailing slashes */
-       while (p && rvbuf[p] == '/') rvbuf[p--] = 0;
+       while (p && rvbuf[p] == '/')
+               rvbuf[p--] = '\0';
        /* strip trailing .git */
        if (p >= 3 && starts_with(&rvbuf[p-3], ".git")) {
-               p -= 3; rvbuf[p--] = 0;
+               p -= 3;
+               rvbuf[p--] = '\0';
        }
        /* strip more trailing slashes if any */
-       while ( p && rvbuf[p] == '/') rvbuf[p--] = 0;
+       while (p && rvbuf[p] == '/')
+               rvbuf[p--] = '\0';
        /* find last slash in the remaining string */
-       rv = strrchr(rvbuf,'/');
+       rv = strrchr(rvbuf, '/');
        if (rv)
                return ++rv;
        return rvbuf;

diff --git a/ui-ssdiff.c b/ui-ssdiff.c
index 7f261ed53a0077fa3fd4a8dab3db1fcdcf247a8c..68c2044dcc75c8ab58df847c36e0debe3665acba 100644 (file)
--- a/ui-ssdiff.c
+++ b/ui-ssdiff.c
@@ -114,11 +114,10 @@ static char *replace_tabs(char *line)
 {
        char *prev_buf = line;
        char *cur_buf;
-       int linelen = strlen(line);
+       size_t linelen = strlen(line);
        int n_tabs = 0;
        int i;
        char *result;
-       char *spaces = "        ";
 
        if (linelen == 0) {
                result = xmalloc(1);
@@ -126,20 +125,23 @@ static char *replace_tabs(char *line)
                return result;
        }
 
-       for (i = 0; i < linelen; i++)
+       for (i = 0; i < linelen; i++) {
                if (line[i] == '\t')
                        n_tabs += 1;
+       }
        result = xmalloc(linelen + n_tabs * 8 + 1);
        result[0] = '\0';
 
-       while (1) {
+       for (;;) {
                cur_buf = strchr(prev_buf, '\t');
                if (!cur_buf) {
                        strcat(result, prev_buf);
                        break;
                } else {
                        strncat(result, prev_buf, cur_buf - prev_buf);
-                       strncat(result, spaces, 8 - (strlen(result) % 8));
+                       linelen = strlen(result);
+                       memset(&result[linelen], ' ', 8 - (linelen % 8));
+                       result[linelen + 8 - (linelen % 8)] = '\0';
                }
                prev_buf = cur_buf + 1;
        }