commit d5ba4851bd8c05ac5a43e302506a1ed67f6be7e7
Author: Nick Mathewson <nickm(a)torproject.org>
Date: Wed Sep 6 09:07:50 2017 -0400
Add buf_t API helpers for using buffers to construct outputs.
---
src/common/buffers.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
src/common/buffers.h | 6 ++++++
2 files changed, 53 insertions(+)
diff --git a/src/common/buffers.c b/src/common/buffers.c
index 50673646d..d7c4e4d8c 100644
--- a/src/common/buffers.c
+++ b/src/common/buffers.c
@@ -710,6 +710,53 @@ buf_add(buf_t *buf, const char *string, size_t string_len)
return (int)buf->datalen;
}
+/** Add a nul-terminated <b>string</b> to <b>buf</b>, not including the
+ * terminating NUL. */
+void
+buf_add_string(buf_t *buf, const char *string)
+{
+ buf_add(buf, string, strlen(string));
+}
+
+/** As tor_snprintf, but write the results into a buf_t */
+void
+buf_add_printf(buf_t *buf, const char *format, ...)
+{
+ va_list ap;
+ va_start(ap,format);
+ buf_add_vprintf(buf, format, ap);
+ va_end(ap);
+}
+
+/** As tor_vsnprintf, but write the results into a buf_t. */
+void
+buf_add_vprintf(buf_t *buf, const char *format, va_list args)
+{
+ /* XXXX Faster implementations are easy enough, but let's optimize later */
+ char *tmp;
+ tor_vasprintf(&tmp, format, args);
+ buf_add(buf, tmp, strlen(tmp));
+ tor_free(tmp);
+}
+
+/** Return a heap-allocated string containing the contents of <b>buf</b>, plus
+ * a NUL byte. If <b>sz_out</b> is provided, set *<b>sz_out</b> to the length
+ * of the returned string, not including the terminating NUL. */
+char *
+buf_extract(buf_t *buf, size_t *sz_out)
+{
+ tor_assert(buf);
+
+ size_t sz = buf_datalen(buf);
+ char *result;
+ result = tor_malloc(sz+1);
+ buf_peek(buf, result, sz);
+ result[sz] = 0;
+ if (sz_out)
+ *sz_out = sz;
+ return result;
+}
+
/** Helper: copy the first <b>string_len</b> bytes from <b>buf</b>
* onto <b>string</b>.
*/
diff --git a/src/common/buffers.h b/src/common/buffers.h
index 5a52b2a81..b05c5b13d 100644
--- a/src/common/buffers.h
+++ b/src/common/buffers.h
@@ -43,6 +43,11 @@ int buf_flush_to_socket(buf_t *buf, tor_socket_t s, size_t sz,
size_t *buf_flushlen);
int buf_add(buf_t *buf, const char *string, size_t string_len);
+void buf_add_string(buf_t *buf, const char *string);
+void buf_add_printf(buf_t *buf, const char *format, ...)
+ CHECK_PRINTF(2, 3);
+void buf_add_vprintf(buf_t *buf, const char *format, va_list args)
+ CHECK_PRINTF(2, 0);
int buf_add_compress(buf_t *buf, struct tor_compress_state_t *state,
const char *data, size_t data_len, int done);
int buf_move_to_buf(buf_t *buf_out, buf_t *buf_in, size_t *buf_flushlen);
@@ -62,6 +67,7 @@ void buf_assert_ok(buf_t *buf);
int buf_find_string_offset(const buf_t *buf, const char *s, size_t n);
void buf_pullup(buf_t *buf, size_t bytes,
const char **head_out, size_t *len_out);
+char *buf_extract(buf_t *buf, size_t *sz_out);
#ifdef BUFFERS_PRIVATE
#ifdef TOR_UNIT_TESTS