util.[ch]: Factor out hex encoding and decoding utilities.

[secnet.git] / util.h

diff --git a/util.h b/util.h
index b44b911189ee0d2e28c8b8df8ffcea91ef987fc1..62642fdb32696dce3b97653b5979ca594749502e 100644 (file)
--- a/util.h
+++ b/util.h
@@ -1,3 +1,22 @@
+/*
+ * This file is part of secnet.
+ * See README for full list of copyright holders.
+ *
+ * secnet is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * secnet is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 3 along with secnet; if not, see
+ * https://www.gnu.org/licenses/gpl.html.
+ */
+
 #ifndef util_h
 #define util_h
 
@@ -23,6 +42,7 @@ extern void buffer_assert_used(struct buffer_if *buffer, cstring_t file,
                               int line);
 extern void buffer_new(struct buffer_if *buffer, int32_t len);
 extern void buffer_init(struct buffer_if *buffer, int32_t max_start_pad);
+extern void buffer_destroy(struct buffer_if *buffer);
 extern void buffer_copy(struct buffer_if *dst, const struct buffer_if *src);
 extern void *buf_append(struct buffer_if *buf, int32_t amount);
 extern void *buf_prepend(struct buffer_if *buf, int32_t amount);
@@ -67,6 +87,24 @@ extern void buffer_readonly_clone(struct buffer_if *n, const struct buffer_if*);
 
 extern void buf_append_string(struct buffer_if *buf, cstring_t s);
 
+extern string_t hex_encode(const uint8_t *bin, int binsize);
+  /* Convert a byte array to hex, returning the result in a freshly allocated
+   * string.
+   */
+
+extern bool_t hex_decode(uint8_t *buffer, int32_t buflen, int32_t *outlen,
+                        cstring_t hb, bool_t allow_odd_nibble);
+  /* Convert a hex string to binary, storing the result in buffer.  If
+   * allow_odd_nibble then it is acceptable if the input is an odd number of
+   * digits, and an additional leading zero digit is assumed; otherwise, this
+   * is not acceptable and the conversion fails.
+   *
+   * The input is processed left to right until it is consumed, the buffer is
+   * full, or an error is encountered in the input.  The length of output
+   * produced is stored in *outlen.  Returns true if the entire input was
+   * processed without error; otherwise false.
+   */
+
 extern void read_mpbin(MP_INT *a, uint8_t *bin, int binsize);
 
 extern char *write_mpstring(MP_INT *a);
@@ -88,6 +126,21 @@ void string_item_to_iaddr(const item_t *item, uint16_t port, union iaddr *ia,
                          const char *desc);
 
 
+/*
+ * SBUF_DEFINE(int nbufs, size_t size);
+ *   // Generates a number of definitions and statements organising
+ *   // nbufs rotating char[size] buffers such that subsequent code
+ *   // may refer to:
+ * char *const SBUF;
+ */
+#define SBUF_DEFINE(nbufs, size)                       \
+    static int static_bufs__bufnum;                    \
+    static char static_bufs__bufs[(nbufs)][(size)];    \
+    static_bufs__bufnum++;                             \
+    static_bufs__bufnum %= (nbufs);                    \
+    static_bufs__bufs[static_bufs__bufnum]
+#define SBUF (static_bufs__bufs[static_bufs__bufnum])
+
 /*----- line-buffered asynch input -----*/
 
 enum async_linebuf_result {
@@ -97,6 +150,8 @@ enum async_linebuf_result {
     async_linebuf_broken,
 };
 
+const char *pollbadbit(int revents); /* returns 0, or bad bit description */
+
 enum async_linebuf_result
 async_linebuf_read(struct pollfd *pfd, struct buffer_if *buf,
                   const char **emsg_out);
@@ -161,6 +216,9 @@ async_linebuf_read(struct pollfd *pfd, struct buffer_if *buf,
 #define MAX(a,b) MINMAX((a),(b),>)
 #define MIN(a,b) MINMAX((a),(b),<)
 
+#define MAX_RAW(a,b) ((a)>(b)?(a):(b))
+#define MIN_RAW(a,b) ((a)<(b)?(a):(b))
+
 static inline bool_t iswouldblock(int e)
     { return e==EWOULDBLOCK || e==EAGAIN; }