X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fbasic%2Fstrv.c;h=c98e956fd92ce7be1cfa5a8e55e0276f77f59163;hp=251031e012c078fdb4f597f3d25d09599edaa923;hb=f5eb2a086bc5d5d36bc2e4755a1d6b508e202250;hpb=7a6781d5aa01c5609232f60bbda7ba9a5bd1f74c

diff --git a/src/basic/strv.c b/src/basic/strv.c
index 251031e01..c98e956fd 100644
--- a/src/basic/strv.c
+++ b/src/basic/strv.c
@@ -87,8 +87,7 @@ void strv_clear(char **l) {
 
 char **strv_free(char **l) {
         strv_clear(l);
-        free(l);
-        return NULL;
+        return mfree(l);
 }
 
 char **strv_free_erase(char **l) {
@@ -431,8 +430,7 @@ char *strv_join_quoted(char **l) {
         return buf;
 
  oom:
-        free(buf);
-        return NULL;
+        return mfree(buf);
 }
 #endif // 0
 
@@ -648,6 +646,17 @@ char **strv_remove(char **l, const char *s) {
 }
 
 char **strv_parse_nulstr(const char *s, size_t l) {
+        /* l is the length of the input data, which will be split at NULs into
+         * elements of the resulting strv. Hence, the number of items in the resulting strv
+         * will be equal to one plus the number of NUL bytes in the l bytes starting at s,
+         * unless s[l-1] is NUL, in which case the final empty string is not stored in
+         * the resulting strv, and length is equal to the number of NUL bytes.
+         *
+         * Note that contrary to a normal nulstr which cannot contain empty strings, because
+         * the input data is terminated by any two consequent NUL bytes, this parser accepts
+         * empty strings in s.
+         */
+
         const char *p;
         unsigned c = 0, i = 0;
         char **v;
@@ -711,6 +720,13 @@ char **strv_split_nulstr(const char *s) {
 
 #if 0 /// UNNEEDED by elogind
 int strv_make_nulstr(char **l, char **p, size_t *q) {
+        /* A valid nulstr with two NULs at the end will be created, but
+         * q will be the length without the two trailing NULs. Thus the output
+         * string is a valid nulstr and can be iterated over using NULSTR_FOREACH,
+         * and can also be parsed by strv_parse_nulstr as long as the length
+         * is provided separately.
+         */
+
         size_t n_allocated = 0, n = 0;
         _cleanup_free_ char *m = NULL;
         char **i;
@@ -723,7 +739,7 @@ int strv_make_nulstr(char **l, char **p, size_t *q) {
 
                 z = strlen(*i);
 
-                if (!GREEDY_REALLOC(m, n_allocated, n + z + 1))
+                if (!GREEDY_REALLOC(m, n_allocated, n + z + 2))
                         return -ENOMEM;
 
                 memcpy(m + n, *i, z + 1);
@@ -734,11 +750,14 @@ int strv_make_nulstr(char **l, char **p, size_t *q) {
                 m = new0(char, 1);
                 if (!m)
                         return -ENOMEM;
-                n = 0;
-        }
+                n = 1;
+        } else
+                /* make sure there is a second extra NUL at the end of resulting nulstr */
+                m[n] = '\0';
 
+        assert(n > 0);
         *p = m;
-        *q = n;
+        *q = n - 1;
 
         m = NULL;
 
@@ -861,8 +880,7 @@ char ***strv_free_free(char ***l) {
         for (i = l; *i; i++)
                 strv_free(*i);
 
-        free(l);
-        return NULL;
+        return mfree(l);
 }
 
 char **strv_skip(char **l, size_t n) {