Add cfw_stream_read_line().

This also adds a caching infrastructure to cfw_stream.

src/stream.c

@@ -24,16 +24,21 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <stdlib.h>
 #include <string.h>
 
 #include "stream.h"
 
+#define BUFFER_SIZE 4096
+
 static bool
 ctor(void *ptr, va_list args)
 {
 	CFWStream *stream = ptr;
 
 	stream->ops = NULL;
+	stream->cache = NULL;
+	stream->cache_len = 0;
 
 	return true;
 }
@@ -53,10 +58,178 @@ cfw_stream_read(void *ptr, void *buf, size_t len)
 	if (stream == NULL || stream->ops == NULL)
 		return -1;
 
-	if ((ret = stream->ops->read(stream, buf, len)) < -1)
-		ret = -1;
+	if (stream->cache == NULL) {
+		if ((ret = stream->ops->read(stream, buf, len)) < -1)
+			ret = -1;
 
-	return ret;
+		return ret;
+	}
+
+	if (len >= stream->cache_len) {
+		ret = stream->cache_len;
+
+		memcpy(buf, stream->cache, stream->cache_len);
+
+		free(stream->cache);
+		stream->cache = NULL;
+		stream->cache_len = 0;
+
+		return ret;
+	} else {
+		char *tmp;
+
+		if ((tmp = malloc(stream->cache_len - len)) == NULL)
+			return -1;
+		memcpy(tmp, stream->cache + len, stream->cache_len - len);
+		memcpy(buf, stream->cache, len);
+
+		free(stream->cache);
+		stream->cache = tmp;
+		stream->cache_len -= len;
+
+		return len;
+	}
+}
+
+CFWString*
+cfw_stream_read_line(void *ptr)
+{
+	CFWStream *stream = ptr;
+	CFWString *ret;
+	char *buf, *ret_str, *new_cache;
+	ssize_t buf_len;
+	size_t i, ret_len;
+
+	/* Look if there is a line or \0 in our cache */
+	if (stream->cache != NULL) {
+		for (i = 0; i < stream->cache_len; i++) {
+			if (stream->cache[i] == '\n' ||
+			    stream->cache[i] == '\0') {
+				ret_len = i;
+				if (i > 0 && stream->cache[i - 1] == '\r')
+					ret_len--;
+
+				ret_str = cfw_strndup(stream->cache, ret_len);
+				if (ret_str == NULL)
+					return NULL;
+
+				ret = cfw_create(cfw_string, NULL);
+				if (ret == NULL) {
+					free(ret_str);
+					return NULL;
+				}
+				cfw_string_set_nocopy(ret, ret_str, ret_len);
+
+				new_cache = malloc(stream->cache_len - i - 1);
+				if (new_cache == NULL)
+					return NULL;
+				memcpy(new_cache, stream->cache + i + 1,
+				    stream->cache_len - i - 1);
+
+				free(stream->cache);
+				stream->cache = new_cache;
+				stream->cache_len -= i + 1;
+
+				return ret;
+			}
+		}
+	}
+
+	/* Read and see if we get a newline or \0 */
+
+	if ((buf = malloc(BUFFER_SIZE)) == NULL)
+		return NULL;
+
+	for (;;) {
+		if (stream->ops->eof(stream)) {
+			free(buf);
+
+			if (stream->cache == NULL)
+				return NULL;
+
+			ret_len = stream->cache_len;
+
+			if (ret_len > 0 && stream->cache[ret_len - 1] == '\r')
+				ret_len--;
+
+			ret_str = cfw_strndup(stream->cache, ret_len);
+			if (ret_str == NULL)
+				return NULL;
+
+			ret = cfw_create(cfw_string, NULL);
+			if (ret == NULL) {
+				free(ret_str);
+				return NULL;
+			}
+			cfw_string_set_nocopy(ret, ret_str, ret_len);
+
+			free(stream->cache);
+			stream->cache = NULL;
+			stream->cache_len = 0;
+
+			return ret;
+		}
+
+		buf_len = stream->ops->read(stream, buf, BUFFER_SIZE);
+		if (buf_len == -1) {
+			free(buf);
+			return NULL;
+		}
+
+		/* Look if there's a newline or \0 */
+		for (i = 0; i < buf_len; i++) {
+			if (buf[i] == '\n' || buf[i] == '\0') {
+				ret_len = stream->cache_len + i;
+
+				if ((ret_str = malloc(ret_len + 1)) == NULL) {
+					/*
+					 * FIXME: We lost the current buffer.
+					 *	  Mark the stream as broken?
+					 */
+					free(buf);
+					return NULL;
+				}
+				memcpy(ret_str, stream->cache,
+				    stream->cache_len);
+				memcpy(ret_str + stream->cache_len, buf, i);
+				if (ret_len > 0 && ret_str[ret_len - 1] == '\r')
+					ret_len--;
+				ret_str[ret_len] = '\0';
+
+				ret = cfw_create(cfw_string, NULL);
+				if (ret == NULL) {
+					free(buf);
+					free(ret_str);
+					return NULL;
+				}
+				cfw_string_set_nocopy(ret, ret_str, ret_len);
+
+				new_cache = malloc(buf_len - i - 1);
+				if (new_cache == NULL) {
+					free(buf);
+					return NULL;
+				}
+				memcpy(new_cache, buf + i + 1, buf_len - i - 1);
+
+				free(stream->cache);
+				stream->cache = new_cache;
+				stream->cache_len = buf_len - i - 1;
+
+				free(buf);
+				return ret;
+			}
+		}
+
+		/* There was no newline or \0 */
+		new_cache = realloc(stream->cache, stream->cache_len + buf_len);
+		if (new_cache == NULL) {
+			free(buf);
+			return NULL;
+		}
+		memcpy(new_cache + stream->cache_len, buf, buf_len);
+		stream->cache = new_cache;
+		stream->cache_len += buf_len;
+	}
 }
 
 bool
@@ -84,6 +257,9 @@ cfw_stream_eof(void *ptr)
 	if (stream == NULL || stream->ops == NULL)
 		return true;
 
+	if (stream->cache != NULL)
+		return false;
+
 	return stream->ops->eof(stream);
 }