commit-tree.c

   1 #include "cache.h"
   2
   3 #include <pwd.h>
   4 #include <time.h>
   5
   6 #define BLOCKING (1ul << 14)
   7 #define ORIG_OFFSET (40)
   8
   9 /*
  10  * Leave space at the beginning to insert the tag
  11  * once we know how big things are.
  12  *
  13  * FIXME! Share the code with "write-tree.c"
  14  */
  15 static void init_buffer(char **bufp, unsigned int *sizep)
  16 {
  17         char *buf = malloc(BLOCKING);
  18         memset(buf, 0, ORIG_OFFSET);
  19         *sizep = ORIG_OFFSET;
  20         *bufp = buf;
  21 }
  22
  23 static void add_buffer(char **bufp, unsigned int *sizep, const char *fmt, ...)
  24 {
  25         char one_line[2048];
  26         va_list args;
  27         int len;
  28         unsigned long alloc, size, newsize;
  29         char *buf;
  30
  31         va_start(args, fmt);
  32         len = vsnprintf(one_line, sizeof(one_line), fmt, args);
  33         va_end(args);
  34         size = *sizep;
  35         newsize = size + len;
  36         alloc = (size + 32767) & ~32767;
  37         buf = *bufp;
  38         if (newsize > alloc) {
  39                 alloc = (newsize + 32767) & ~32767;
  40                 buf = realloc(buf, alloc);
  41                 *bufp = buf;
  42         }
  43         *sizep = newsize;
  44         memcpy(buf + size, one_line, len);
  45 }
  46
  47 static int prepend_integer(char *buffer, unsigned val, int i)
  48 {
  49         buffer[--i] = '\0';
  50         do {
  51                 buffer[--i] = '0' + (val % 10);
  52                 val /= 10;
  53         } while (val);
  54         return i;
  55 }
  56
  57 static void finish_buffer(char *tag, char **bufp, unsigned int *sizep)
  58 {
  59         int taglen;
  60         int offset;
  61         char *buf = *bufp;
  62         unsigned int size = *sizep;
  63
  64         offset = prepend_integer(buf, size - ORIG_OFFSET, ORIG_OFFSET);
  65         taglen = strlen(tag);
  66         offset -= taglen;
  67         buf += offset;
  68         size -= offset;
  69         memcpy(buf, tag, taglen);
  70
  71         *bufp = buf;
  72         *sizep = size;
  73 }
  74
  75 static void remove_special(char *p)
  76 {
  77         char c;
  78         char *dst = p;
  79
  80         for (;;) {
  81                 c = *p;
  82                 p++;
  83                 switch(c) {
  84                 case '\n': case '<': case '>':
  85                         continue;
  86                 }
  87                 *dst++ = c;
  88                 if (!c)
  89                         break;
  90         }
  91 }
  92
  93 /*
  94  * Having more than two parents may be strange, but hey, there's
  95  * no conceptual reason why the file format couldn't accept multi-way
  96  * merges. It might be the "union" of several packages, for example.
  97  *
  98  * I don't really expect that to happen, but this is here to make
  99  * it clear that _conceptually_ it's ok..
 100  */
 101 #define MAXPARENT (16)
 102
 103 int main(int argc, char **argv)
 104 {
 105         int i, len;
 106         int parents = 0;
 107         unsigned char tree_sha1[20];
 108         unsigned char parent_sha1[MAXPARENT][20];
 109         char *gecos, *realgecos;
 110         char *email, realemail[1000];
 111         char *date, *realdate;
 112         char comment[1000];
 113         struct passwd *pw;
 114         time_t now;
 115         char *buffer;
 116         unsigned int size;
 117
 118         if (argc < 2 || get_sha1_hex(argv[1], tree_sha1) < 0)
 119                 usage("commit-tree <sha1> [-p <sha1>]* < changelog");
 120
 121         for (i = 2; i < argc; i += 2) {
 122                 char *a, *b;
 123                 a = argv[i]; b = argv[i+1];
 124                 if (!b || strcmp(a, "-p") || get_sha1_hex(b, parent_sha1[parents]))
 125                         usage("commit-tree <sha1> [-p <sha1>]* < changelog");
 126                 parents++;
 127         }
 128         if (!parents)
 129                 fprintf(stderr, "Committing initial tree %s\n", argv[1]);
 130         pw = getpwuid(getuid());
 131         if (!pw)
 132                 usage("You don't exist. Go away!");
 133         realgecos = pw->pw_gecos;
 134         len = strlen(pw->pw_name);
 135         memcpy(realemail, pw->pw_name, len);
 136         realemail[len] = '@';
 137         gethostname(realemail+len+1, sizeof(realemail)-len-1);
 138         time(&now);
 139         realdate = ctime(&now);
 140
 141         gecos = getenv("COMMITTER_NAME") ? : realgecos;
 142         email = getenv("COMMITTER_EMAIL") ? : realemail;
 143         date = getenv("COMMITTER_DATE") ? : realdate;
 144
 145         remove_special(gecos); remove_special(realgecos);
 146         remove_special(email); remove_special(realemail);
 147         remove_special(date); remove_special(realdate);
 148
 149         init_buffer(&buffer, &size);
 150         add_buffer(&buffer, &size, "tree %s\n", sha1_to_hex(tree_sha1));
 151
 152         /*
 153          * NOTE! This ordering means that the same exact tree merged with a
 154          * different order of parents will be a _different_ changeset even
 155          * if everything else stays the same.
 156          */
 157         for (i = 0; i < parents; i++)
 158                 add_buffer(&buffer, &size, "parent %s\n", sha1_to_hex(parent_sha1[i]));
 159
 160         /* Person/date information */
 161         add_buffer(&buffer, &size, "author %s <%s> %s\n", gecos, email, date);
 162         add_buffer(&buffer, &size, "committer %s <%s> %s\n\n", realgecos, realemail, realdate);
 163
 164         /* And add the comment */
 165         while (fgets(comment, sizeof(comment), stdin) != NULL)
 166                 add_buffer(&buffer, &size, "%s", comment);
 167
 168         finish_buffer("commit ", &buffer, &size);
 169
 170         write_sha1_file(buffer, size);
 171         return 0;
 172 }