mktree.con commit Added Packing Heursitics IRC writeup. (b116b29)
   1/*
   2 * GIT - the stupid content tracker
   3 *
   4 * Copyright (c) Junio C Hamano, 2006
   5 */
   6#include "cache.h"
   7#include "strbuf.h"
   8#include "quote.h"
   9#include "tree.h"
  10
  11static struct treeent {
  12        unsigned mode;
  13        unsigned char sha1[20];
  14        int len;
  15        char name[FLEX_ARRAY];
  16} **entries;
  17static int alloc, used;
  18
  19static void append_to_tree(unsigned mode, unsigned char *sha1, char *path)
  20{
  21        struct treeent *ent;
  22        int len = strlen(path);
  23        if (strchr(path, '/'))
  24                die("path %s contains slash", path);
  25
  26        if (alloc <= used) {
  27                alloc = alloc_nr(used);
  28                entries = xrealloc(entries, sizeof(*entries) * alloc);
  29        }
  30        ent = entries[used++] = xmalloc(sizeof(**entries) + len + 1);
  31        ent->mode = mode;
  32        ent->len = len;
  33        memcpy(ent->sha1, sha1, 20);
  34        memcpy(ent->name, path, len+1);
  35}
  36
  37static int ent_compare(const void *a_, const void *b_)
  38{
  39        struct treeent *a = *(struct treeent **)a_;
  40        struct treeent *b = *(struct treeent **)b_;
  41        return base_name_compare(a->name, a->len, a->mode,
  42                                 b->name, b->len, b->mode);
  43}
  44
  45static void write_tree(unsigned char *sha1)
  46{
  47        char *buffer;
  48        unsigned long size, offset;
  49        int i;
  50
  51        qsort(entries, used, sizeof(*entries), ent_compare);
  52        size = 100;
  53        for (size = i = 0; i < used; i++)
  54                size += 32 + entries[i]->len;
  55        buffer = xmalloc(size);
  56        offset = 0;
  57
  58        for (i = 0; i < used; i++) {
  59                struct treeent *ent = entries[i];
  60
  61                if (offset + ent->len + 100 < size) {
  62                        size = alloc_nr(offset + ent->len + 100);
  63                        buffer = xrealloc(buffer, size);
  64                }
  65                offset += sprintf(buffer + offset, "%o ", ent->mode);
  66                offset += sprintf(buffer + offset, "%s", ent->name);
  67                buffer[offset++] = 0;
  68                memcpy(buffer + offset, ent->sha1, 20);
  69                offset += 20;
  70        }
  71        write_sha1_file(buffer, offset, tree_type, sha1);
  72}
  73
  74static const char mktree_usage[] = "mktree [-z]";
  75
  76int main(int ac, char **av)
  77{
  78        struct strbuf sb;
  79        unsigned char sha1[20];
  80        int line_termination = '\n';
  81
  82        setup_git_directory();
  83
  84        while ((1 < ac) && av[1][0] == '-') {
  85                char *arg = av[1];
  86                if (!strcmp("-z", arg))
  87                        line_termination = 0;
  88                else
  89                        usage(mktree_usage);
  90                ac--;
  91                av++;
  92        }
  93
  94        strbuf_init(&sb);
  95        while (1) {
  96                int len;
  97                char *ptr, *ntr;
  98                unsigned mode;
  99                char type[20];
 100                char *path;
 101
 102                read_line(&sb, stdin, line_termination);
 103                if (sb.eof)
 104                        break;
 105                len = sb.len;
 106                ptr = sb.buf;
 107                /* Input is non-recursive ls-tree output format
 108                 * mode SP type SP sha1 TAB name
 109                 */
 110                mode = strtoul(ptr, &ntr, 8);
 111                if (ptr == ntr || !ntr || *ntr != ' ')
 112                        die("input format error: %s", sb.buf);
 113                ptr = ntr + 1; /* type */
 114                ntr = strchr(ptr, ' ');
 115                if (!ntr || sb.buf + len <= ntr + 41 ||
 116                    ntr[41] != '\t' ||
 117                    get_sha1_hex(ntr + 1, sha1))
 118                        die("input format error: %s", sb.buf);
 119                if (sha1_object_info(sha1, type, NULL))
 120                        die("object %s unavailable", sha1_to_hex(sha1));
 121                *ntr++ = 0; /* now at the beginning of SHA1 */
 122                if (strcmp(ptr, type))
 123                        die("object type %s mismatch (%s)", ptr, type);
 124                ntr += 41; /* at the beginning of name */
 125                if (line_termination && ntr[0] == '"')
 126                        path = unquote_c_style(ntr, NULL);
 127                else
 128                        path = ntr;
 129
 130                append_to_tree(mode, sha1, path);
 131
 132                if (path != ntr)
 133                        free(path);
 134        }
 135        write_tree(sha1);
 136        puts(sha1_to_hex(sha1));
 137        exit(0);
 138}