First commit

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 149 insertions, 0 deletions

diff --git a/libpatch_parse_ed_patch.c b/libpatch_parse_ed_patch.c
new file mode 100644
index 0000000..f3dec51
--- /dev/null
+++ b/libpatch_parse_ed_patch.c
@@ -0,0 +1,149 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+
+static size_t
+hunk_head(const char *text, size_t len, size_t *first, size_t *last)
+{
+	size_t off = 1, r;
+	off += r = libpatch_get_zu__(&text[off], len - off, first);
+	if (!r)
+		return 0;
+	if (off < len && text[off] == ',') {
+		off += 1;
+		off += r = libpatch_get_zu__(&text[off], len - off, last);
+		if (!r)
+			return 0;
+	} else {
+		*last = *first;
+	}
+	return off;
+}
+
+
+int
+libpatch_parse_ed_patch(const char *text, size_t textlen, size_t *textend,
+                        struct libpatch_patch **patch, size_t *patchlen)
+{
+	const char *patchtext = text;
+	size_t len = 0, size = 0, off, line, last, count;
+	int in_hunk = 0, can_continue = 0, has_patch = 0;
+	size_t *hunks = NULL, *new;
+	size_t nhunks = 0, hunks_size = 0;
+	struct libpatch_patch *patchcopy = NULL;
+	size_t patchcopysize = 0;
+
+	*patch = NULL;
+	*patchlen = 0;
+
+	while ((len = libpatch_next_line__(&text, &textlen, len))) {
+		if (can_continue) {
+			can_continue = 0;
+			if (len == 1 && text[0] == 'a') {
+				in_hunk = 1;
+			} else if (len == 1 && text[0] == 'i') {
+				goto garbage; /* TODO */
+			} else if (len >= 5 && !strncmp(text, "s/", 2) && text[len - 1] == '/') {
+				if (*patchlen < 2 || !IS_LINE((*patch)[*patchlen - 2].type))
+					goto garbage;
+				/* TODO add support for more weird alternatives */
+				if (!(len == 5 && !strncmp(text, "s/.//", len)) &&
+				    !(len == 6 && !strncmp(text, "s/^.//", len)) &&
+				    !(len == 6 && !strncmp(text, "s/\\.//", len)) &&
+				    !(len == 7 && !strncmp(text, "s/^\\.//", len)))
+					goto garbage;
+				(*patch)[*patchlen - 2].text_offset += 1;
+				(*patch)[*patchlen - 2].text_length -= 1;
+				APPEND_STRING(len, LIBPATCH_PATCH_SYNTACTICAL);
+			} else {
+				goto else_if;
+			}
+			APPEND_STRING(len, LIBPATCH_PATCH_SYNTACTICAL);
+
+		} else else_if: if (in_hunk && len == 1 && text[0] == '.') {
+			APPEND_STRING(len, LIBPATCH_PATCH_SYNTACTICAL);
+			in_hunk = 0;
+			can_continue = 1;
+
+		} else if (in_hunk) {
+			APPEND_STRING(0, LIBPATCH_PATCH_FILE2_ONLY);
+			(*patch)[*patchlen - 1].file1_lineno = line;
+
+		} else if (len >= 5 && !strncmp(text, "diff ", 5)) {
+			if (has_patch && textend)
+				break;
+			if (libpatch_reverse_hunks__(*patch, *patchlen, hunks, nhunks, &patchcopy, &patchcopysize))
+				goto fail;
+			nhunks = 0;
+			APPEND_STRING(5, LIBPATCH_PATCH_DIFF_LINE);
+
+		} else if (len >= 2 && isdigit(text[0])) {
+			off = hunk_head(text, len, &line, &last);
+			if (len - off != 1)
+				goto garbage;
+			if (!line && last)
+				goto garbage;
+			else if (!line)
+				count = 0, line = 1;
+			else if (last < line)
+				goto garbage;
+			else
+				count = last - line + 1;
+
+			if (text[off] == 'd') {
+				APPEND_NO_TEXT(LIBPATCH_PATCH_HUNK_WITH_DELETION);
+				(*patch)[*patchlen - 1].first_line = line;
+				(*patch)[*patchlen - 1].line_count = count;
+			} else if (text[off] == 'a') {
+				APPEND_NO_TEXT(LIBPATCH_PATCH_HUNK);
+				in_hunk = 1;
+			} else if (text[off] == 'c') {
+				APPEND_NO_TEXT(LIBPATCH_PATCH_HUNK_WITH_DELETION);
+				(*patch)[*patchlen - 1].first_line = line;
+				(*patch)[*patchlen - 1].line_count = count;
+				in_hunk = 1;
+			} else if (text[off] == 'i') {
+				goto garbage; /* TODO */
+			} else {
+				goto garbage;
+			}
+
+			if (nhunks == hunks_size) {
+				if (hunks_size > SIZE_MAX / sizeof(*hunks) - 16)
+					goto enomem;
+				new = realloc(hunks, (hunks_size += 16) * sizeof(*hunks));
+				if (!new)
+					goto fail;
+				hunks = new;
+			}
+			hunks[nhunks++] = *patchlen - 1;
+			has_patch = 1;
+
+		} else {
+		garbage:
+			APPEND_STRING(0, LIBPATCH_PATCH_GARBAGE);
+			if (len == textlen)
+				(*patch)[*patchlen - 1].lf_terminated = 0;
+		}
+	}
+
+	if (libpatch_reverse_hunks__(*patch, *patchlen, hunks, nhunks, &patchcopy, &patchcopysize))
+		goto fail;
+
+	if (textend)
+		*textend = (size_t)(text - patchtext);
+
+	free(patchcopy);
+	free(hunks);
+	return 0;
+
+enomem:
+	errno = ENOMEM;
+fail:
+	free(patchcopy);
+	free(hunks);
+	free(*patch);
+	*patch = NULL;
+	*patchlen = 0;
+	return -1;
+}