projects / thirdparty / git.git / blame
| Commit | Line | Data |
|---|---|---|
| 86436c28 JH |
1 | #include "cache.h" |
| 2 | #include "diff.h" | |
| 3 | ||
| 4 | static char *diff_cmd = "diff -L 'k/%s' -L 'l/%s' "; | |
| 5 | static char *diff_opts = "-p -u"; | |
| 6 | static char *diff_arg_forward = " - '%s'"; | |
| 7 | static char *diff_arg_reverse = " '%s' -"; | |
| 8 | ||
| 9 | void prepare_diff_cmd(void) | |
| 10 | { | |
| 11 | /* | |
| 12 | * Default values above are meant to match the | |
| 13 | * Linux kernel development style. Examples of | |
| 14 | * alternative styles you can specify via environment | |
| 15 | * variables are: | |
| 16 | * | |
| 17 | * GIT_DIFF_CMD="diff -L '%s' -L '%s'" | |
| 18 | * GIT_DIFF_OPTS="-c"; | |
| 19 | */ | |
| 20 | diff_cmd = getenv("GIT_DIFF_CMD") ? : diff_cmd; | |
| 21 | diff_opts = getenv("GIT_DIFF_OPTS") ? : diff_opts; | |
| 22 | } | |
| 23 | ||
| 24 | /* Help to copy the thing properly quoted for the shell safety. | |
| 25 | * any single quote is replaced with '\'', and the caller is | |
| 26 | * expected to enclose the result within a single quote pair. | |
| 27 | * | |
| 28 | * E.g. | |
| 29 | * original sq_expand result | |
| 30 | * name ==> name ==> 'name' | |
| 31 | * a b ==> a b ==> 'a b' | |
| 32 | * a'b ==> a'\''b ==> 'a'\''b' | |
| 33 | */ | |
| 34 | static char *sq_expand(const char *src) | |
| 35 | { | |
| 36 | static char *buf = NULL; | |
| 37 | int cnt, c; | |
| 38 | const char *cp; | |
| 39 | char *bp; | |
| 40 | ||
| 41 | /* count bytes needed to store the quoted string. */ | |
| 42 | for (cnt = 1, cp = src; *cp; cnt++, cp++) | |
| 43 | if (*cp == '\'') | |
| 44 | cnt += 3; | |
| 45 | ||
| 46 | if (! (buf = malloc(cnt))) | |
| 47 | return buf; | |
| 48 | bp = buf; | |
| 49 | while ((c = *src++)) { | |
| 50 | if (c != '\'') | |
| 51 | *bp++ = c; | |
| 52 | else { | |
| 53 | bp = strcpy(bp, "'\\''"); | |
| 54 | bp += 4; | |
| 55 | } | |
| 56 | } | |
| 57 | *bp = 0; | |
| 58 | return buf; | |
| 59 | } | |
| 60 | ||
| 61 | void show_differences(const char *name, /* filename on the filesystem */ | |
| 62 | const char *label, /* diff label to use */ | |
| 63 | void *old_contents, /* contents in core */ | |
| 64 | unsigned long long old_size, /* size in core */ | |
| 65 | int reverse /* 0: diff core file | |
| 66 | 1: diff file core */) | |
| 67 | { | |
| 68 | FILE *f; | |
| 69 | char *name_sq = sq_expand(name); | |
| 70 | const char *label_sq = (name != label) ? sq_expand(label) : name_sq; | |
| 71 | char *diff_arg = reverse ? diff_arg_reverse : diff_arg_forward; | |
| 72 | int cmd_size = strlen(name_sq) + strlen(label_sq) * 2 + | |
| 73 | strlen(diff_cmd) + strlen(diff_opts) + strlen(diff_arg); | |
| 74 | char *cmd = malloc(cmd_size); | |
| 75 | int next_at; | |
| 76 | ||
| 77 | fflush(stdout); | |
| 78 | next_at = snprintf(cmd, cmd_size, diff_cmd, label_sq, label_sq); | |
| 79 | next_at += snprintf(cmd+next_at, cmd_size-next_at, "%s", diff_opts); | |
| 80 | next_at += snprintf(cmd+next_at, cmd_size-next_at, diff_arg, name_sq); | |
| 81 | f = popen(cmd, "w"); | |
| 82 | if (old_size) | |
| 83 | fwrite(old_contents, old_size, 1, f); | |
| 84 | pclose(f); | |
| 85 | if (label_sq != name_sq) | |
| 86 | free((void*)label_sq); /* constness */ | |
| 87 | free(name_sq); | |
| 88 | free(cmd); | |
| 89 | } | |
| 90 | ||
| 91 | void show_diff_empty(const unsigned char *sha1, | |
| 92 | const char *name, | |
| 93 | int reverse) | |
| 94 | { | |
| 95 | char *old; | |
| 96 | unsigned long int size; | |
| 97 | unsigned char type[20]; | |
| 98 | ||
| 99 | old = read_sha1_file(sha1, type, &size); | |
| 100 | if (! old) { | |
| 101 | error("unable to read blob object for %s (%s)", name, | |
| 102 | sha1_to_hex(sha1)); | |
| 103 | return; | |
| 104 | } | |
| 105 | show_differences("/dev/null", name, old, size, reverse); | |
| 106 | } |