core: add vlc_MakeTmpFile() helper

to avoid messy and duplicated code creating temporary files.

include/vlc_fs.h

@@ -99,6 +99,21 @@ VLC_API int vlc_openat(int fd, const char *filename, int flags, ...) VLC_USED;
 
 VLC_API int vlc_mkstemp( char * );
 
+/**
+ * Temporary file creation helper
+ *
+ * Creates a unique temporary file, using config_GetTempPath() to determine the
+ * directory in which to create it, and using vlc_mkstemp() for the creation.
+ *
+ * Note, the returned `path` pointer must be free'd with free(), except when
+ * the returned file descriptor is -1 indicating error, where is it undefined.
+ *
+ * @param path [OUT] full path of the created file.
+ * @param filetemplate filename template, which must end with a sequence of 'XXXXXX'.
+ * @return file descriptor, or -1 on error.
+ */
+VLC_API int vlc_MakeTmpFile( char **path, const char *filetemplate ) VLC_USED;
+
 /**
  * Duplicates a file descriptor. The new file descriptor has the close-on-exec
  * descriptor flag preset.

src/libvlccore.sym

@@ -432,6 +432,7 @@ vlc_loaddir
 vlc_lstat
 vlc_mkdir
 vlc_mkstemp
+vlc_MakeTmpFile
 vlc_open
 vlc_openat
 vlc_memfd

src/text/filesystem.c

@@ -30,6 +30,7 @@
 
 #include <vlc_common.h>
 #include <vlc_fs.h>
+#include <vlc_configuration.h>
 #include <vlc_sort.h>
 
 #include <assert.h>
@@ -242,3 +243,21 @@ VLC_WEAK int vlc_mkstemp(char *template)
     errno = EEXIST;
     return -1;
 }
+
+int vlc_MakeTmpFile( char **path, const char *filetemplate )
+{
+    char *tmpdir = config_GetTempPath();
+    if (tmpdir == NULL)
+        return -1;
+
+    if (asprintf(path, "%s"DIR_SEP"%s", tmpdir, filetemplate) < 0) {
+        free(tmpdir);
+        return -1;
+    }
+    free(tmpdir);
+
+    int fd = vlc_mkstemp(*path);
+    if (fd == -1)
+        free(*path);
+    return fd;
+}