[FFmpeg-devel] [PATCH 5/5] libavfilter/vf_frei0r.c: Use UTF-8 version of getenv()

[Andreas Rheinhardt]

From: Nil Admirari <nil-admirari at mailo.com>

---
This version has the advantage that duplicating the string
is checked and that av_strdup(NULL) (whose behaviour is undocumented)
is avoided.

Here is a branch complete with these changes:
https://github.com/mkver/FFmpeg/commits/getenv
The Windows version has not been tested.

 libavfilter/vf_frei0r.c | 20 ++++++++++++++++----
 libavutil/getenv_utf8.h | 12 ++++++++++++
 2 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/libavfilter/vf_frei0r.c b/libavfilter/vf_frei0r.c
index f11ae6e55c..46b4175ba2 100644
--- a/libavfilter/vf_frei0r.c
+++ b/libavfilter/vf_frei0r.c
@@ -31,6 +31,7 @@
 #include "libavutil/avstring.h"
 #include "libavutil/common.h"
 #include "libavutil/eval.h"
+#include "libavutil/getenv_utf8.h"
 #include "libavutil/imgutils.h"
 #include "libavutil/internal.h"
 #include "libavutil/mathematics.h"
@@ -204,13 +205,19 @@ static av_cold int frei0r_init(AVFilterContext *ctx,
     }
 
     /* see: http://frei0r.dyne.org/codedoc/html/group__pluglocations.html */
-    if ((path = av_strdup(getenv("FREI0R_PATH")))) {
+    path = getenv_utf8("FREI0R_PATH");
+    if (path) {
 #ifdef _WIN32
         const char *separator = ";";
 #else
         const char *separator = ":";
 #endif
         char *p, *ptr = NULL;
+
+        path = getenv_make_writable(path);
+        if (!path)
+            return AVERROR(ENOMEM);
+
         for (p = path; p = av_strtok(p, separator, &ptr); p = NULL) {
             /* add additional trailing slash in case it is missing */
             char *p1 = av_asprintf("%s/", p);
@@ -231,12 +238,17 @@ static av_cold int frei0r_init(AVFilterContext *ctx,
         if (ret < 0)
             return ret;
     }
-    if (!s->dl_handle && (path = getenv("HOME"))) {
+    if (!s->dl_handle && (path = getenv_utf8("HOME"))) {
         char *prefix = av_asprintf("%s/.frei0r-1/lib/", path);
-        if (!prefix)
-            return AVERROR(ENOMEM);
+        if (!prefix) {
+            ret = AVERROR(ENOMEM);
+            goto home_path_end;
+        }
         ret = load_path(ctx, &s->dl_handle, prefix, dl_name);
         av_free(prefix);
+
+    home_path_end:
+        freeenv_utf8(path);
         if (ret < 0)
             return ret;
     }
diff --git a/libavutil/getenv_utf8.h b/libavutil/getenv_utf8.h
index 03d108eed4..37a778b7aa 100644
--- a/libavutil/getenv_utf8.h
+++ b/libavutil/getenv_utf8.h
@@ -59,6 +59,11 @@ static inline void freeenv_utf8(char *var)
     av_free(var);
 }
 
+static inline char *getenv_make_writable(char *var)
+{
+    return var;
+}
+
 #else
 
 static inline char *getenv_utf8(const char *varname)
@@ -70,6 +75,11 @@ static inline void freeenv_utf8(char *var)
 {
 }
 
+static inline char *getenv_make_writable(const char *var)
+{
+    return av_strdup(var);
+}
+
 #endif // _WIN32
 
 #else
@@ -78,6 +88,8 @@ static inline void freeenv_utf8(char *var)
 
 #define freeenv_utf8(x) ((void) 0)
 
+#define getenv_make_writable(x) NULL
+
 #endif // HAVE_GETENV
 
 #endif // AVUTIL_GETENV_UTF8_H
-- 
2.34.1