[PATCH weston 1/4] shared: Add a function to prefix filenames with datadir

[Derek Foreman]

Currently we look for png files in their install directory, and we
manufacture filenames with string pasting at compile time.

This new function will allow overriding the compile time setting with
the env var WESTON_DATA_DIR so we can do neat tricks like allow our
test suite to pass when we haven't yet installed icons system-wide.

Signed-off-by: Derek Foreman <derekf at osg.samsung.com>
---
 shared/file-util.c | 17 +++++++++++++++++
 shared/file-util.h |  3 +++
 2 files changed, 20 insertions(+)

diff --git a/shared/file-util.c b/shared/file-util.c
index 979a3811..758c8dcc 100644
--- a/shared/file-util.c
+++ b/shared/file-util.c
@@ -31,6 +31,7 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
+#include <stdlib.h>
 
 #include "file-util.h"
 
@@ -119,3 +120,19 @@ file_create_dated(const char *path_prefix, const char *suffix,
 
 	return fdopen(fd, "w");
 }
+
+char *
+file_name_with_datadir(const char *filename)
+{
+	const char *base = getenv("WESTON_DATA_DIR");
+	char *out;
+	int len;
+
+	if (base)
+		len = asprintf(&out, "%s/%s", base, filename);
+	else
+		len = asprintf(&out, "%s/weston/%s", DATADIR, filename);
+
+	if (len == -1) return NULL;
+	return out;
+}
diff --git a/shared/file-util.h b/shared/file-util.h
index f639c446..dbda07a8 100644
--- a/shared/file-util.h
+++ b/shared/file-util.h
@@ -36,6 +36,9 @@ FILE *
 file_create_dated(const char *path_prefix, const char *suffix,
 		  char *name_out, size_t name_len);
 
+char *
+file_name_with_datadir(const char *);
+
 #ifdef  __cplusplus
 }
 #endif
-- 
2.14.3