Add lilv_create_temporary_directory()

2 files changed, 51 insertions, 0 deletions

diff --git a/src/filesystem.c b/src/filesystem.c
index dc72d93..27476ec 100644
--- a/src/filesystem.c
+++ b/src/filesystem.c
@@ -339,6 +339,46 @@ lilv_dir_for_each(const char* path,
 #endif
 }
 
+char*
+lilv_create_temporary_directory(const char* pattern)
+{
+#ifdef _WIN32
+	static const char chars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
+	static const int  n_chars = sizeof(chars) - 1;
+
+	const size_t pattern_len = strlen(pattern);
+	if (pattern_len < 7 || strcmp(pattern + pattern_len - 6, "XXXXXX")) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	char* const  tmpdir           = lilv_temp_directory_path();
+	char* const  path_pattern     = lilv_path_join(tmpdir, pattern);
+	const size_t path_pattern_len = strlen(path_pattern);
+	char* const  suffix           = path_pattern + path_pattern_len - 6;
+
+	free(tmpdir);
+
+	for (unsigned attempt = 0; attempt < 128; ++attempt) {
+		for (unsigned i = 0; i < 6; ++i) {
+			suffix[i] = chars[rand() % n_chars];
+		}
+
+		if (!mkdir(path_pattern, 0700)) {
+			return path_pattern;
+		}
+	}
+
+	return NULL;
+#else
+	char* const tmpdir       = lilv_temp_directory_path();
+	char* const path_pattern = lilv_path_join(tmpdir, pattern);
+
+	free(tmpdir);
+	return mkdtemp(path_pattern); // NOLINT (not a leak)
+#endif
+}
+
 int
 lilv_create_directories(const char* dir_path)
 {
diff --git a/src/filesystem.h b/src/filesystem.h
index 09b8b5f..f5ac35c 100644
--- a/src/filesystem.h
+++ b/src/filesystem.h
@@ -129,6 +129,17 @@ lilv_dir_for_each(const char* path,
                   void (*f)(const char* path, const char* name, void* data));
 
 /**
+   Create a unique temporary directory.
+
+   The last six characters of `pattern` must be `XXXXXX` and will be replaced
+   with random characters.  This works roughly like mkdtemp, except the pattern
+   should only be a directory name, not a full path.  The returned path will be
+   in a suitable system temporary directory.
+*/
+char*
+lilv_create_temporary_directory(const char* pattern);
+
+/**
    Create the directory `dir_path` and any parent directories if necessary.
 
    @return Zero on success, or an `errno` error code.