hex-escape: (en|de)code strings to/from restricted character set

The character set is chosen to be suitable for pathnames, and the same
as that used by contrib/nmbug

[With additions by Jani Nikula]

1 files changed, 41 insertions, 0 deletions

diff --git a/util/hex-escape.h b/util/hex-escape.h
new file mode 100644
index 00000000..5182042e
--- /dev/null
+++ b/util/hex-escape.h
@@ -0,0 +1,41 @@
+#ifndef _HEX_ESCAPE_H
+#define _HEX_ESCAPE_H
+
+typedef enum hex_status {
+    HEX_SUCCESS = 0,
+    HEX_SYNTAX_ERROR,
+    HEX_OUT_OF_MEMORY
+} hex_status_t;
+
+/*
+ * The API for hex_encode() and hex_decode() is modelled on that for
+ * getline.
+ *
+ * If 'out' points to a NULL pointer a char array of the appropriate
+ * size is allocated using talloc, and out_size is updated.
+ *
+ * If 'out' points to a non-NULL pointer, it assumed to describe an
+ * existing char array, with the size given in *out_size.  This array
+ * may be resized by talloc_realloc if needed; in this case *out_size
+ * will also be updated.
+ *
+ * Note that it is an error to pass a NULL pointer for any parameter
+ * of these routines.
+ */
+
+hex_status_t
+hex_encode (void *talloc_ctx, const char *in, char **out,
+            size_t *out_size);
+
+hex_status_t
+hex_decode (void *talloc_ctx, const char *in, char **out,
+            size_t *out_size);
+
+/*
+ * Non-allocating hex decode to decode 's' in-place. The length of the
+ * result is always equal to or shorter than the length of the
+ * original.
+ */
+hex_status_t
+hex_decode_inplace (char *s);
+#endif