nspawn: support ephemeral boots from images

[elogind.git] / src / basic / strv.c

diff --git a/src/basic/strv.c b/src/basic/strv.c
index ba4d697b106959cc6054992ad11c7f374bb564a5..c98e956fd92ce7be1cfa5a8e55e0276f77f59163 100644 (file)
--- 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) {
@@ -139,16 +138,16 @@ char **strv_new_ap(const char *x, va_list ap) {
         va_list aq;
 
         /* As a special trick we ignore all listed strings that equal
-         * (const char*) -1. This is supposed to be used with the
+         * STRV_IGNORE. This is supposed to be used with the
          * STRV_IFNOTNULL() macro to include possibly NULL strings in
          * the string list. */
 
         if (x) {
-                n = x == (const char*) -1 ? 0 : 1;
+                n = x == STRV_IGNORE ? 0 : 1;
 
                 va_copy(aq, ap);
                 while ((s = va_arg(aq, const char*))) {
-                        if (s == (const char*) -1)
+                        if (s == STRV_IGNORE)
                                 continue;
 
                         n++;
@@ -162,7 +161,7 @@ char **strv_new_ap(const char *x, va_list ap) {
                 return NULL;
 
         if (x) {
-                if (x != (const char*) -1) {
+                if (x != STRV_IGNORE) {
                         a[i] = strdup(x);
                         if (!a[i])
                                 goto fail;
@@ -171,7 +170,7 @@ char **strv_new_ap(const char *x, va_list ap) {
 
                 while ((s = va_arg(ap, const char*))) {
 
-                        if (s == (const char*) -1)
+                        if (s == STRV_IGNORE)
                                 continue;
 
                         a[i] = strdup(s);
@@ -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;
 
@@ -816,9 +835,8 @@ char **strv_reverse(char **l) {
         if (n <= 1)
                 return l;
 
-        for (i = 0; i < n / 2; i++) {
+        for (i = 0; i < n / 2; i++)
                 SWAP_TWO(l[i], l[n-1-i]);
-        }
 
         return l;
 }
@@ -847,7 +865,7 @@ bool strv_fnmatch(char* const* patterns, const char *s, int flags) {
         char* const* p;
 
         STRV_FOREACH(p, patterns)
-                if (fnmatch(*p, s, 0) == 0)
+                if (fnmatch(*p, s, flags) == 0)
                         return true;
 
         return false;
@@ -862,8 +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) {
@@ -889,7 +906,7 @@ int strv_extend_n(char ***l, const char *value, size_t n) {
         if (n == 0)
                 return 0;
 
-        /* Adds the value value n times to l */
+        /* Adds the value n times to l */
 
         k = strv_length(*l);