1 files changed, 289 insertions, 0 deletions
diff --git a/lib/buffer.c b/lib/buffer.c
new file mode 100644
index 0000000..1dba7dd
--- /dev/null
+++ b/lib/buffer.c
@@ -0,0 +1,289 @@
+/*
+ * No copyright is claimed.  This code is in the public domain; do with
+ * it what you wish.
+ *
+ * Written by Karel Zak <kzak@redhat.com>
+ */
+#include "buffer.h"
+#include "mbsalign.h"
+
+void ul_buffer_reset_data(struct ul_buffer *buf)
+{
+	if (buf->begin)
+		buf->begin[0] = '\0';
+	buf->end = buf->begin;
+
+	if (buf->ptrs && buf->nptrs)
+		memset(buf->ptrs, 0, buf->nptrs * sizeof(char *));
+}
+
+void ul_buffer_free_data(struct ul_buffer *buf)
+{
+	assert(buf);
+
+	free(buf->begin);
+	buf->begin = NULL;
+	buf->end = NULL;
+	buf->sz = 0;
+
+	free(buf->ptrs);
+	buf->ptrs = NULL;
+	buf->nptrs = 0;
+
+	free(buf->encoded);
+	buf->encoded = NULL;
+	buf->encoded_sz = 0;
+}
+
+void ul_buffer_set_chunksize(struct ul_buffer *buf, size_t sz)
+{
+	buf->chunksize = sz;
+}
+
+int ul_buffer_is_empty(struct ul_buffer *buf)
+{
+	return buf->begin == buf->end;
+}
+
+int ul_buffer_save_pointer(struct ul_buffer *buf, unsigned short ptr_idx)
+{
+	if (ptr_idx >= buf->nptrs) {
+		char **tmp = realloc(buf->ptrs, (ptr_idx + 1) * sizeof(char *));
+
+		if (!tmp)
+			return -EINVAL;
+		buf->ptrs = tmp;
+		buf->nptrs = ptr_idx + 1;
+	}
+
+	buf->ptrs[ptr_idx] = buf->end;
+	return 0;
+}
+
+
+char *ul_buffer_get_pointer(struct ul_buffer *buf, unsigned short ptr_idx)
+{
+	if (ptr_idx < buf->nptrs)
+		return buf->ptrs[ptr_idx];
+	return NULL;
+}
+
+/* returns length from begin to the pointer */
+size_t ul_buffer_get_pointer_length(struct ul_buffer *buf, unsigned short ptr_idx)
+{
+	char *ptr = ul_buffer_get_pointer(buf, ptr_idx);
+
+	if (ptr && ptr > buf->begin)
+		return ptr - buf->begin;
+	return 0;
+}
+
+/* returns width of data in safe encoding (from the begin to the pointer) */
+size_t ul_buffer_get_safe_pointer_width(struct ul_buffer *buf, unsigned short ptr_idx)
+{
+	size_t len = ul_buffer_get_pointer_length(buf, ptr_idx);
+
+	if (!len)
+		return 0;
+
+	return mbs_safe_nwidth(buf->begin, len, NULL);
+}
+
+void ul_buffer_refer_string(struct ul_buffer *buf, char *str)
+{
+	if (buf->sz)
+		ul_buffer_free_data(buf);
+	buf->begin = str;
+	buf->sz = str ? strlen(str) : 0;
+	buf->end = buf->begin ? buf->begin + buf->sz : buf->begin;
+}
+
+int ul_buffer_alloc_data(struct ul_buffer *buf, size_t sz)
+{
+	char *tmp;
+	size_t len = 0;
+
+	assert(buf);
+
+	if (sz <= buf->sz)
+		return 0;
+
+	if (buf->end && buf->begin)
+		len = buf->end - buf->begin;
+
+	if (buf->chunksize)
+		sz = ((sz + buf->chunksize) / buf->chunksize) * buf->chunksize + 1;
+
+	tmp = realloc(buf->begin, sz);
+	if (!tmp)
+		return -ENOMEM;
+
+	buf->begin = tmp;
+	buf->end = buf->begin + len;
+	buf->sz = sz;
+
+	memset(buf->end, '\0', sz - len);
+
+	return 0;
+}
+
+int ul_buffer_append_data(struct ul_buffer *buf, const char *data, size_t sz)
+{
+	size_t maxsz = 0;
+
+	if (!buf)
+		return -EINVAL;
+	if (!data || !*data)
+		return 0;
+
+	if (buf->begin && buf->end)
+		maxsz = buf->sz - (buf->end - buf->begin);
+
+	if (maxsz <= sz + 1) {
+		int rc = ul_buffer_alloc_data(buf, buf->sz + sz + 1);
+		if (rc)
+			return rc;
+	}
+	if (!buf->end)
+		return -EINVAL;	/* make static analyzers happy */
+
+	memcpy(buf->end, data, sz);
+	buf->end += sz;
+	*buf->end = '\0';	/* make sure it's terminated */
+	return 0;
+}
+
+int ul_buffer_append_string(struct ul_buffer *buf, const char *str)
+{
+	if (!str)
+		return 0;
+
+	return ul_buffer_append_data(buf, str, strlen(str));
+}
+
+int ul_buffer_append_ntimes(struct ul_buffer *buf, size_t n, const char *str)
+{
+	size_t i;
+	size_t len = strlen(str);
+
+	for (i = 0; len && i < n; i++) {
+		int rc = ul_buffer_append_data(buf, str, len);
+		if (rc)
+			return rc;
+	}
+	return 0;
+}
+
+int ul_buffer_set_data(struct ul_buffer *buf, const char *data, size_t sz)
+{
+	ul_buffer_reset_data(buf);
+	return ul_buffer_append_data(buf, data, sz);
+}
+
+char *ul_buffer_get_data(struct ul_buffer *buf, size_t *sz, size_t *width)
+{
+	if (sz)
+		*sz = buf->end - buf->begin;
+	if (width)
+		*width = buf->begin && *buf->begin ? mbs_width(buf->begin) : 0;
+	return buf->begin;
+}
+
+/* size of allocated area (!= size of stored data */
+size_t ul_buffer_get_bufsiz(struct ul_buffer *buf)
+{
+	return buf->sz;
+}
+
+/* encode data by mbs_safe_encode() to avoid control and non-printable chars */
+char *ul_buffer_get_safe_data(struct ul_buffer *buf, size_t *sz, size_t *width, const char *safechars)
+{
+	char *data = ul_buffer_get_data(buf, NULL, NULL);
+	size_t encsz, wsz = 0;
+	char *res = NULL;
+
+	if (!data)
+		goto nothing;
+
+	encsz = mbs_safe_encode_size(buf->sz) + 1;
+	if (encsz > buf->encoded_sz) {
+		char *tmp = realloc(buf->encoded, encsz);
+		if (!tmp)
+			goto nothing;
+		buf->encoded = tmp;
+		buf->encoded_sz = encsz;
+	}
+
+	res = mbs_safe_encode_to_buffer(data, &wsz, buf->encoded, safechars);
+	if (!res || !wsz || wsz == (size_t) -1)
+		goto nothing;
+
+	if (width)
+		*width = wsz;
+	if (sz)
+		*sz = strlen(res);
+	return res;
+nothing:
+	if (width)
+		*width = 0;
+	if (sz)
+		*sz = 0;
+	return NULL;
+}
+
+
+#ifdef TEST_PROGRAM_BUFFER
+
+enum {
+	PTR_AAA  = 0,
+	PTR_BBB,
+};
+
+int main(void)
+{
+	struct ul_buffer buf = UL_INIT_BUFFER;
+	char *str;
+	size_t sz = 0;
+
+	ul_buffer_set_chunksize(&buf, 16);
+
+	ul_buffer_append_string(&buf, "AAA");
+	ul_buffer_append_data(&buf, "=", 1);
+	ul_buffer_append_string(&buf, "aaa");
+	ul_buffer_save_pointer(&buf, PTR_AAA);
+
+	ul_buffer_append_data(&buf, ",", 1);
+	ul_buffer_append_string(&buf, "BBB");
+	ul_buffer_append_string(&buf, "=");
+	ul_buffer_append_string(&buf, "bbb");
+	ul_buffer_save_pointer(&buf, PTR_BBB);
+
+	str = ul_buffer_get_data(&buf, &sz, NULL);
+	printf("data [%zu] '%s'\n", sz, str);
+
+	printf(" pointer data len: AAA=%zu, BBB=%zu\n",
+			ul_buffer_get_pointer_length(&buf, PTR_AAA),
+			ul_buffer_get_pointer_length(&buf, PTR_BBB));
+	printf(" pointer data width: AAA=%zu, BBB=%zu\n",
+			ul_buffer_get_safe_pointer_width(&buf, PTR_AAA),
+			ul_buffer_get_safe_pointer_width(&buf, PTR_BBB));
+
+	ul_buffer_reset_data(&buf);
+	ul_buffer_append_string(&buf, "This is really long string to test the buffer function.");
+	ul_buffer_save_pointer(&buf, PTR_AAA);
+	ul_buffer_append_string(&buf, " YES!");
+	str = ul_buffer_get_data(&buf, &sz, NULL);
+	printf("data [%zu] '%s'\n", sz, str);
+	printf(" pointer data len: AAA=%zu\n", ul_buffer_get_pointer_length(&buf, PTR_AAA));
+
+	ul_buffer_free_data(&buf);
+	str = strdup("foo");
+	ul_buffer_refer_string(&buf, str);
+	ul_buffer_append_data(&buf, ",", 1);
+	ul_buffer_append_string(&buf, "bar");
+	str = ul_buffer_get_data(&buf, &sz, NULL);
+	printf("data [%zu] '%s'\n", sz, str);
+
+	ul_buffer_free_data(&buf);
+}
+#endif /* TEST_PROGRAM_BUFFER */