xdiff-interface.c

   1 #include "cache.h"
   2 #include "xdiff-interface.h"
   3
   4 static int parse_num(char **cp_p, int *num_p)
   5 {
   6         char *cp = *cp_p;
   7         int num = 0;
   8         int read_some;
   9
  10         while ('0' <= *cp && *cp <= '9')
  11                 num = num * 10 + *cp++ - '0';
  12         if (!(read_some = cp - *cp_p))
  13                 return -1;
  14         *cp_p = cp;
  15         *num_p = num;
  16         return 0;
  17 }
  18
  19 int parse_hunk_header(char *line, int len,
  20                       int *ob, int *on,
  21                       int *nb, int *nn)
  22 {
  23         char *cp;
  24         cp = line + 4;
  25         if (parse_num(&cp, ob)) {
  26         bad_line:
  27                 return error("malformed diff output: %s", line);
  28         }
  29         if (*cp == ',') {
  30                 cp++;
  31                 if (parse_num(&cp, on))
  32                         goto bad_line;
  33         }
  34         else
  35                 *on = 1;
  36         if (*cp++ != ' ' || *cp++ != '+')
  37                 goto bad_line;
  38         if (parse_num(&cp, nb))
  39                 goto bad_line;
  40         if (*cp == ',') {
  41                 cp++;
  42                 if (parse_num(&cp, nn))
  43                         goto bad_line;
  44         }
  45         else
  46                 *nn = 1;
  47         return -!!memcmp(cp, " @@", 3);
  48 }
  49
  50 static void consume_one(void *priv_, char *s, unsigned long size)
  51 {
  52         struct xdiff_emit_state *priv = priv_;
  53         char *ep;
  54         while (size) {
  55                 unsigned long this_size;
  56                 ep = memchr(s, '\n', size);
  57                 this_size = (ep == NULL) ? size : (ep - s + 1);
  58                 priv->consume(priv, s, this_size);
  59                 size -= this_size;
  60                 s += this_size;
  61         }
  62 }
  63
  64 int xdiff_outf(void *priv_, mmbuffer_t *mb, int nbuf)
  65 {
  66         struct xdiff_emit_state *priv = priv_;
  67         int i;
  68
  69         for (i = 0; i < nbuf; i++) {
  70                 if (mb[i].ptr[mb[i].size-1] != '\n') {
  71                         /* Incomplete line */
  72                         priv->remainder = xrealloc(priv->remainder,
  73                                                    priv->remainder_size +
  74                                                    mb[i].size);
  75                         memcpy(priv->remainder + priv->remainder_size,
  76                                mb[i].ptr, mb[i].size);
  77                         priv->remainder_size += mb[i].size;
  78                         continue;
  79                 }
  80
  81                 /* we have a complete line */
  82                 if (!priv->remainder) {
  83                         consume_one(priv, mb[i].ptr, mb[i].size);
  84                         continue;
  85                 }
  86                 priv->remainder = xrealloc(priv->remainder,
  87                                            priv->remainder_size +
  88                                            mb[i].size);
  89                 memcpy(priv->remainder + priv->remainder_size,
  90                        mb[i].ptr, mb[i].size);
  91                 consume_one(priv, priv->remainder,
  92                             priv->remainder_size + mb[i].size);
  93                 free(priv->remainder);
  94                 priv->remainder = NULL;
  95                 priv->remainder_size = 0;
  96         }
  97         if (priv->remainder) {
  98                 consume_one(priv, priv->remainder, priv->remainder_size);
  99                 free(priv->remainder);
 100                 priv->remainder = NULL;
 101                 priv->remainder_size = 0;
 102         }
 103         return 0;
 104 }
 105
 106 int read_mmfile(mmfile_t *ptr, const char *filename)
 107 {
 108         struct stat st;
 109         FILE *f;
 110         size_t sz;
 111
 112         if (stat(filename, &st))
 113                 return error("Could not stat %s", filename);
 114         if ((f = fopen(filename, "rb")) == NULL)
 115                 return error("Could not open %s", filename);
 116         sz = xsize_t(st.st_size);
 117         ptr->ptr = xmalloc(sz);
 118         if (fread(ptr->ptr, sz, 1, f) != 1)
 119                 return error("Could not read %s", filename);
 120         fclose(f);
 121         ptr->size = sz;
 122         return 0;
 123 }
 124
 125 #define FIRST_FEW_BYTES 8000
 126 int buffer_is_binary(const char *ptr, unsigned long size)
 127 {
 128         if (FIRST_FEW_BYTES < size)
 129                 size = FIRST_FEW_BYTES;
 130         return !!memchr(ptr, 0, size);
 131 }