Handle decryption when exporting

1 files changed, 50 insertions, 3 deletions

diff --git a/src/main.c b/src/main.c
index 1593db5..10805f2 100644
--- a/src/main.c
+++ b/src/main.c
@@ -252,9 +252,19 @@ static void __strbuild(char *buf, int size,
 	assert(len >= 0);
 }
 
-/* Convenience wrapper for __strbuild. */
+/* Convenience wrappers for __strbuild. */
 #define strbuild(buf, fmt, ...) \
 	__strbuild(buf, sizeof(buf), __FILE__, __LINE__, fmt, __VA_ARGS__)
+#define strbuild_with_size(buf, size, fmt, ...)				\
+	__strbuild(buf, size, __FILE__, __LINE__, fmt, __VA_ARGS__)
+
+static int str_has_suffix(const char *str, const char *suffix)
+{
+	int str_len = strlen(str);
+	int suffix_len = strlen(suffix);
+	return ((str_len > suffix_len)
+		&& (strcmp(str + str_len - suffix_len, suffix) == 0));
+}
 
 /* Compute something that identifies the content of FILE. Algorithm by Dan
    Bernstein from http://www.cse.yorku.ca/~oz/hash.html via
@@ -381,6 +391,38 @@ static void ftag_file_get_extension(char *out, int size, const char *file)
 	sqlite3_close(db);
 }
 
+/* Get the path to FILE in the ftag database. */
+static void ftag_file_get_path(char *out, int size, const char *file)
+{
+	struct stat st;
+	int rc;
+	/* look for the encrypted version first */
+	strbuild_with_size(out, size, "%s/files/%s.gpg", FTAG_ROOT, file);
+	rc = stat(out, &st);
+	if (rc == 0) {
+		return;
+	}
+	else if (rc == -1 && errno != ENOENT) {
+		fprintf(stderr, "stat: %s:", out);
+		perror("");
+		exit(EXIT_FAILURE);
+	}
+	/* look for the clear version after */
+	out[strlen(out) - 4] = '\0'; /* remove ".gpg" extension */
+	rc = stat(out, &st);
+	if (rc == 0) {
+		return;
+	}
+	else if (rc == -1 && errno != ENOENT) {
+		fprintf(stderr, "stat: %s:", out);
+		perror("");
+		exit(EXIT_FAILURE);
+	}
+	fprintf(stderr,
+		"ftag export: cannot find \"%s\" in the database\n", file);
+	exit(EXIT_FAILURE);
+}
+
 static void ftag_export(int argc, char **argv)
 {
 	if (argc != 1) {
@@ -412,12 +454,17 @@ static void ftag_export(int argc, char **argv)
 	while ((line_len = getline(&line, &line_size, stdin)) != -1) {
 		remove_ending_newline(line);
 		ftag_file_get_extension(extension, sizeof(extension), line);
-		strbuild(in, "%s/files/%s", FTAG_ROOT, line);
+		ftag_file_get_path(in, sizeof(in), line);
+
 		if (strlen(extension) > 0)
 			strbuild(out, "%s/%s.%s", tmp_dir, line, extension);
 		else
 			strbuild(out, "%s/%s", tmp_dir, line);
-		copy_file(in, out);
+
+		if (str_has_suffix(in, ".gpg"))
+			copy_file_with_encryption(in, out, DECRYPT);
+		else
+			copy_file(in, out);
 	}
 	free(line);