diff options
Diffstat (limited to 'builtin/patch-id.c')
| -rw-r--r-- | builtin/patch-id.c | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/builtin/patch-id.c b/builtin/patch-id.c new file mode 100644 index 0000000000..77db8739b5 --- /dev/null +++ b/builtin/patch-id.c @@ -0,0 +1,201 @@ +#include "builtin.h" + +static void flush_current_id(int patchlen, unsigned char *id, unsigned char *result) +{ + char name[50]; + + if (!patchlen) + return; + + memcpy(name, sha1_to_hex(id), 41); + printf("%s %s\n", sha1_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 void flush_one_hunk(unsigned char *result, git_SHA_CTX *ctx) +{ + unsigned char hash[20]; + unsigned short carry = 0; + int i; + + git_SHA1_Final(hash, ctx); + git_SHA1_Init(ctx); + /* 20-byte sum, with carry */ + for (i = 0; i < 20; ++i) { + carry += result[i] + hash[i]; + result[i] = carry; + carry >>= 8; + } +} + +static int get_one_patchid(unsigned char *next_sha1, unsigned char *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); + hashclr(result); + + while (strbuf_getwholeline(line_buf, stdin, '\n') != EOF) { + char *line = line_buf->buf; + char *p = line; + int len; + + if (!memcmp(line, "diff-tree ", 10)) + p += 10; + else if (!memcmp(line, "commit ", 7)) + p += 7; + else if (!memcmp(line, "From ", 5)) + p += 5; + else if (!memcmp(line, "\\ ", 2) && 12 < strlen(line)) + continue; + + if (!get_sha1_hex(p, next_sha1)) { + found_next = 1; + break; + } + + /* Ignore commit comments */ + if (!patchlen && memcmp(line, "diff ", 5)) + continue; + + /* Parsing diff header? */ + if (before == -1) { + if (!memcmp(line, "index ", 6)) + continue; + else if (!memcmp(line, "--- ", 4)) + before = after = 1; + else if (!isalpha(line[0])) + break; + } + + /* Looking for a valid hunk header? */ + if (before == 0 && after == 0) { + if (!memcmp(line, "@@ -", 4)) { + /* Parse next hunk, but ignore line numbers. */ + scan_hunk_header(line, &before, &after); + continue; + } + + /* Split at the end of the patch. */ + if (memcmp(line, "diff ", 5)) + 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) + hashclr(next_sha1); + + flush_one_hunk(result, &ctx); + + return patchlen; +} + +static void generate_id_list(int stable) +{ + unsigned char sha1[20], n[20], result[20]; + int patchlen; + struct strbuf line_buf = STRBUF_INIT; + + hashclr(sha1); + while (!feof(stdin)) { + patchlen = get_one_patchid(n, result, &line_buf, stable); + flush_current_id(patchlen, sha1, result); + hashcpy(sha1, n); + } + strbuf_release(&line_buf); +} + +static const char patch_id_usage[] = "git patch-id [--stable | --unstable] < patch"; + +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; +} |