add various escaping/path handling utility functions

This is a partial combination of two systemd commits:

5926cccae202f1b8869017d4bdaf9e9ce371bba6
4fe88d28a4cfa504c1f2362d4a7030fae4c4af29

...and provides functions needed for the changes that were added
in commit 6284c1ca41dca85e968e8d304cdc154c5a46d6d2

Signed-off-by: Ian Stakenvicius <axs@gentoo.org>

2 files changed, 48 insertions, 0 deletions

diff --git a/src/libudev/strv.c b/src/libudev/strv.c
index 041e20d700..45fb6b24a2 100644
--- a/src/libudev/strv.c
+++ b/src/libudev/strv.c
@@ -142,6 +142,52 @@ char **strv_new(const char *x, ...) {
         return r;
 }
 
+int strv_push(char ***l, char *value) {
+        char **c;
+        char *v;
+        unsigned n;
+
+        if (!value)
+                return 0;
+
+        v = strdup(value);
+        if (!v)
+                return -ENOMEM;
+
+        n = strv_length(*l);
+        c = realloc(*l, sizeof(char*) * (n + 2));
+        if (!c) {
+                free(v);
+        if (!c)
+                return -ENOMEM;
+        }
+
+        c[n] = v;
+        c[n] = value;
+        c[n+1] = NULL;
+
+        *l = c;
+        return 0;
+}
+ 
+int strv_extend(char ***l, const char *value) {
+        char *v;
+        int r;
+
+        if (!value)
+                return 0;
+
+        v = strdup(value);
+        if (!v)
+                return -ENOMEM;
+
+        r = strv_push(l, v);
+        if (r < 0)
+                free(v);
+
+        return r;
+}
+
 char **strv_uniq(char **l) {
         char **i;
 
diff --git a/src/libudev/strv.h b/src/libudev/strv.h
index d9e0e1c20b..ba2bc2f589 100644
--- a/src/libudev/strv.h
+++ b/src/libudev/strv.h
@@ -37,6 +37,8 @@ char **strv_copy(char * const *l);
 unsigned strv_length(char * const *l) _pure_;
 
 char **strv_remove(char **l, const char *s);
+int strv_push(char ***l, char *value);
+int strv_extend(char ***l, const char *value);
 char **strv_uniq(char **l);
 
 char **strv_new(const char *x, ...) _sentinel_;