about summary refs log tree commit diff
path: root/third_party/git/builtin/patch-id.c
diff options
context:
space:
mode:
Diffstat (limited to 'third_party/git/builtin/patch-id.c')
-rw-r--r--third_party/git/builtin/patch-id.c184
1 files changed, 184 insertions, 0 deletions
diff --git a/third_party/git/builtin/patch-id.c b/third_party/git/builtin/patch-id.c
new file mode 100644
index 000000000000..bd28b80b2d0f
--- /dev/null
+++ b/third_party/git/builtin/patch-id.c
@@ -0,0 +1,184 @@
+#include "builtin.h"
+#include "config.h"
+#include "diff.h"
+
+static void flush_current_id(int patchlen, struct object_id *id, struct object_id *result)
+{
+	char name[50];
+
+	if (!patchlen)
+		return;
+
+	memcpy(name, oid_to_hex(id), GIT_SHA1_HEXSZ + 1);
+	printf("%s %s\n", oid_to_hex(result), name);
+}
+
+static int remove_space(char *line)
+{
+	char *src = line;
+	char *dst = line;
+	unsigned char c;
+
+	while ((c = *src++) != '\0') {
+		if (!isspace(c))
+			*dst++ = c;
+	}
+	return dst - line;
+}
+
+static int scan_hunk_header(const char *p, int *p_before, int *p_after)
+{
+	static const char digits[] = "0123456789";
+	const char *q, *r;
+	int n;
+
+	q = p + 4;
+	n = strspn(q, digits);
+	if (q[n] == ',') {
+		q += n + 1;
+		n = strspn(q, digits);
+	}
+	if (n == 0 || q[n] != ' ' || q[n+1] != '+')
+		return 0;
+
+	r = q + n + 2;
+	n = strspn(r, digits);
+	if (r[n] == ',') {
+		r += n + 1;
+		n = strspn(r, digits);
+	}
+	if (n == 0)
+		return 0;
+
+	*p_before = atoi(q);
+	*p_after = atoi(r);
+	return 1;
+}
+
+static int get_one_patchid(struct object_id *next_oid, struct object_id *result,
+			   struct strbuf *line_buf, int stable)
+{
+	int patchlen = 0, found_next = 0;
+	int before = -1, after = -1;
+	git_SHA_CTX ctx;
+
+	git_SHA1_Init(&ctx);
+	oidclr(result);
+
+	while (strbuf_getwholeline(line_buf, stdin, '\n') != EOF) {
+		char *line = line_buf->buf;
+		const char *p = line;
+		int len;
+
+		if (!skip_prefix(line, "diff-tree ", &p) &&
+		    !skip_prefix(line, "commit ", &p) &&
+		    !skip_prefix(line, "From ", &p) &&
+		    starts_with(line, "\\ ") && 12 < strlen(line))
+			continue;
+
+		if (!get_oid_hex(p, next_oid)) {
+			found_next = 1;
+			break;
+		}
+
+		/* Ignore commit comments */
+		if (!patchlen && !starts_with(line, "diff "))
+			continue;
+
+		/* Parsing diff header?  */
+		if (before == -1) {
+			if (starts_with(line, "index "))
+				continue;
+			else if (starts_with(line, "--- "))
+				before = after = 1;
+			else if (!isalpha(line[0]))
+				break;
+		}
+
+		/* Looking for a valid hunk header?  */
+		if (before == 0 && after == 0) {
+			if (starts_with(line, "@@ -")) {
+				/* Parse next hunk, but ignore line numbers.  */
+				scan_hunk_header(line, &before, &after);
+				continue;
+			}
+
+			/* Split at the end of the patch.  */
+			if (!starts_with(line, "diff "))
+				break;
+
+			/* Else we're parsing another header.  */
+			if (stable)
+				flush_one_hunk(result, &ctx);
+			before = after = -1;
+		}
+
+		/* If we get here, we're inside a hunk.  */
+		if (line[0] == '-' || line[0] == ' ')
+			before--;
+		if (line[0] == '+' || line[0] == ' ')
+			after--;
+
+		/* Compute the sha without whitespace */
+		len = remove_space(line);
+		patchlen += len;
+		git_SHA1_Update(&ctx, line, len);
+	}
+
+	if (!found_next)
+		oidclr(next_oid);
+
+	flush_one_hunk(result, &ctx);
+
+	return patchlen;
+}
+
+static void generate_id_list(int stable)
+{
+	struct object_id oid, n, result;
+	int patchlen;
+	struct strbuf line_buf = STRBUF_INIT;
+
+	oidclr(&oid);
+	while (!feof(stdin)) {
+		patchlen = get_one_patchid(&n, &result, &line_buf, stable);
+		flush_current_id(patchlen, &oid, &result);
+		oidcpy(&oid, &n);
+	}
+	strbuf_release(&line_buf);
+}
+
+static const char patch_id_usage[] = "git patch-id [--stable | --unstable]";
+
+static int git_patch_id_config(const char *var, const char *value, void *cb)
+{
+	int *stable = cb;
+
+	if (!strcmp(var, "patchid.stable")) {
+		*stable = git_config_bool(var, value);
+		return 0;
+	}
+
+	return git_default_config(var, value, cb);
+}
+
+int cmd_patch_id(int argc, const char **argv, const char *prefix)
+{
+	int stable = -1;
+
+	git_config(git_patch_id_config, &stable);
+
+	/* If nothing is set, default to unstable. */
+	if (stable < 0)
+		stable = 0;
+
+	if (argc == 2 && !strcmp(argv[1], "--stable"))
+		stable = 1;
+	else if (argc == 2 && !strcmp(argv[1], "--unstable"))
+		stable = 0;
+	else if (argc != 1)
+		usage(patch_id_usage);
+
+	generate_id_list(stable);
+	return 0;
+}