builtin-rerere.c

   1 #include "builtin.h"
   2 #include "cache.h"
   3 #include "string-list.h"
   4 #include "rerere.h"
   5 #include "xdiff/xdiff.h"
   6 #include "xdiff-interface.h"
   7
   8 static const char git_rerere_usage[] =
   9 "git rerere [clear | status | diff | gc]";
  10
  11 /* these values are days */
  12 static int cutoff_noresolve = 15;
  13 static int cutoff_resolve = 60;
  14
  15 static const char *rr_path(const char *name, const char *file)
  16 {
  17         return git_path("rr-cache/%s/%s", name, file);
  18 }
  19
  20 static time_t rerere_created_at(const char *name)
  21 {
  22         struct stat st;
  23         return stat(rr_path(name, "preimage"), &st) ? (time_t) 0 : st.st_mtime;
  24 }
  25
  26 static int has_resolution(const char *name)
  27 {
  28         struct stat st;
  29         return !stat(rr_path(name, "postimage"), &st);
  30 }
  31
  32 static void unlink_rr_item(const char *name)
  33 {
  34         unlink(rr_path(name, "thisimage"));
  35         unlink(rr_path(name, "preimage"));
  36         unlink(rr_path(name, "postimage"));
  37         rmdir(git_path("rr-cache/%s", name));
  38 }
  39
  40 static int git_rerere_gc_config(const char *var, const char *value, void *cb)
  41 {
  42         if (!strcmp(var, "gc.rerereresolved"))
  43                 cutoff_resolve = git_config_int(var, value);
  44         else if (!strcmp(var, "gc.rerereunresolved"))
  45                 cutoff_noresolve = git_config_int(var, value);
  46         else
  47                 return git_default_config(var, value, cb);
  48         return 0;
  49 }
  50
  51 static void garbage_collect(struct string_list *rr)
  52 {
  53         struct string_list to_remove = { NULL, 0, 0, 1 };
  54         DIR *dir;
  55         struct dirent *e;
  56         int i, cutoff;
  57         time_t now = time(NULL), then;
  58
  59         git_config(git_rerere_gc_config, NULL);
  60         dir = opendir(git_path("rr-cache"));
  61         while ((e = readdir(dir))) {
  62                 const char *name = e->d_name;
  63                 if (name[0] == '.' &&
  64                     (name[1] == '\0' || (name[1] == '.' && name[2] == '\0')))
  65                         continue;
  66                 then = rerere_created_at(name);
  67                 if (!then)
  68                         continue;
  69                 cutoff = (has_resolution(name)
  70                           ? cutoff_resolve : cutoff_noresolve);
  71                 if (then < now - cutoff * 86400)
  72                         string_list_append(name, &to_remove);
  73         }
  74         for (i = 0; i < to_remove.nr; i++)
  75                 unlink_rr_item(to_remove.items[i].string);
  76         string_list_clear(&to_remove, 0);
  77 }
  78
  79 static int outf(void *dummy, mmbuffer_t *ptr, int nbuf)
  80 {
  81         int i;
  82         for (i = 0; i < nbuf; i++)
  83                 if (write_in_full(1, ptr[i].ptr, ptr[i].size) != ptr[i].size)
  84                         return -1;
  85         return 0;
  86 }
  87
  88 static int diff_two(const char *file1, const char *label1,
  89                 const char *file2, const char *label2)
  90 {
  91         xpparam_t xpp;
  92         xdemitconf_t xecfg;
  93         xdemitcb_t ecb;
  94         mmfile_t minus, plus;
  95
  96         if (read_mmfile(&minus, file1) || read_mmfile(&plus, file2))
  97                 return 1;
  98
  99         printf("--- a/%s\n+++ b/%s\n", label1, label2);
 100         fflush(stdout);
 101         xpp.flags = XDF_NEED_MINIMAL;
 102         memset(&xecfg, 0, sizeof(xecfg));
 103         xecfg.ctxlen = 3;
 104         ecb.outf = outf;
 105         xdi_diff(&minus, &plus, &xpp, &xecfg, &ecb);
 106
 107         free(minus.ptr);
 108         free(plus.ptr);
 109         return 0;
 110 }
 111
 112 int cmd_rerere(int argc, const char **argv, const char *prefix)
 113 {
 114         struct string_list merge_rr = { NULL, 0, 0, 1 };
 115         int i, fd;
 116
 117         if (argc < 2)
 118                 return rerere();
 119
 120         fd = setup_rerere(&merge_rr);
 121         if (fd < 0)
 122                 return 0;
 123
 124         if (!strcmp(argv[1], "clear")) {
 125                 for (i = 0; i < merge_rr.nr; i++) {
 126                         const char *name = (const char *)merge_rr.items[i].util;
 127                         if (!has_resolution(name))
 128                                 unlink_rr_item(name);
 129                 }
 130                 unlink(git_path("rr-cache/MERGE_RR"));
 131         } else if (!strcmp(argv[1], "gc"))
 132                 garbage_collect(&merge_rr);
 133         else if (!strcmp(argv[1], "status"))
 134                 for (i = 0; i < merge_rr.nr; i++)
 135                         printf("%s\n", merge_rr.items[i].string);
 136         else if (!strcmp(argv[1], "diff"))
 137                 for (i = 0; i < merge_rr.nr; i++) {
 138                         const char *path = merge_rr.items[i].string;
 139                         const char *name = (const char *)merge_rr.items[i].util;
 140                         diff_two(rr_path(name, "preimage"), path, path, path);
 141                 }
 142         else
 143                 usage(git_rerere_usage);
 144
 145         string_list_clear(&merge_rr, 1);
 146         return 0;
 147 }