X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=fd.c;h=bdba2765a0fe3c6be12a9b32679bd79c267c6eb3;hp=2e59bc95111d4e94daac0cf070ddf48b0dde4c81;hb=60ef885705932a682097ad2b9f2379282d814e79;hpb=de7b5b177b8ad295820bd14c00b049fd8a5ec21f

diff --git a/fd.c b/fd.c
index 2e59bc95..bdba2765 100644
--- a/fd.c
+++ b/fd.c
@@ -177,6 +177,51 @@ int read_nonblock(int fd, void *buf, size_t sz, fd_set *rfds, size_t *num_bytes)
 	return readv_nonblock(fd, &iov, 1, rfds, num_bytes);
 }
 
+/**
+ * Read a buffer and check its content for a pattern.
+ *
+ * \param fd The file descriptor to receive from.
+ * \param pattern The expected pattern.
+ * \param bufsize The size of the internal buffer.
+ *
+ * This function tries to read at most \a bufsize bytes from the non-blocking
+ * file descriptor \a fd. If at least \p strlen(\a pattern) bytes have been
+ * received, the beginning of the received buffer is compared with \a pattern,
+ * ignoring case.
+ *
+ * \return Positive if \a pattern was received, negative on errors, zero if no data
+ * was available to read.
+ *
+ * \sa \ref read_nonblock(), \sa strncasecmp(3).
+ */
+int read_pattern(int fd, const char *pattern, size_t bufsize, fd_set *rfds)
+{
+	size_t n, len;
+	char *buf = para_malloc(bufsize + 1);
+	int ret = read_nonblock(fd, buf, bufsize, rfds, &n);
+
+	buf[n] = '\0';
+	if (ret < 0)
+		goto out;
+	ret = 0;
+	if (n == 0)
+		goto out;
+	ret = -E_READ_PATTERN;
+	len = strlen(pattern);
+	if (n < len)
+		goto out;
+	if (strncasecmp(buf, pattern, len) != 0)
+		goto out;
+	ret = 1;
+out:
+	if (ret < 0) {
+		PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
+		PARA_NOTICE_LOG("recvd %zu bytes: %s\n", n, buf);
+	}
+	free(buf);
+	return ret;
+}
+
 /**
  * Check whether a file exists.
  *