Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "xdiff-interface.h"
   3#include "strbuf.h"
   4
   5struct xdiff_emit_state {
   6        xdiff_emit_consume_fn consume;
   7        void *consume_callback_data;
   8        struct strbuf remainder;
   9};
  10
  11static int parse_num(char **cp_p, int *num_p)
  12{
  13        char *cp = *cp_p;
  14        int num = 0;
  15        int read_some;
  16
  17        while ('0' <= *cp && *cp <= '9')
  18                num = num * 10 + *cp++ - '0';
  19        if (!(read_some = cp - *cp_p))
  20                return -1;
  21        *cp_p = cp;
  22        *num_p = num;
  23        return 0;
  24}
  25
  26int parse_hunk_header(char *line, int len,
  27                      int *ob, int *on,
  28                      int *nb, int *nn)
  29{
  30        char *cp;
  31        cp = line + 4;
  32        if (parse_num(&cp, ob)) {
  33        bad_line:
  34                return error("malformed diff output: %s", line);
  35        }
  36        if (*cp == ',') {
  37                cp++;
  38                if (parse_num(&cp, on))
  39                        goto bad_line;
  40        }
  41        else
  42                *on = 1;
  43        if (*cp++ != ' ' || *cp++ != '+')
  44                goto bad_line;
  45        if (parse_num(&cp, nb))
  46                goto bad_line;
  47        if (*cp == ',') {
  48                cp++;
  49                if (parse_num(&cp, nn))
  50                        goto bad_line;
  51        }
  52        else
  53                *nn = 1;
  54        return -!!memcmp(cp, " @@", 3);
  55}
  56
  57static void consume_one(void *priv_, char *s, unsigned long size)
  58{
  59        struct xdiff_emit_state *priv = priv_;
  60        char *ep;
  61        while (size) {
  62                unsigned long this_size;
  63                ep = memchr(s, '\n', size);
  64                this_size = (ep == NULL) ? size : (ep - s + 1);
  65                priv->consume(priv->consume_callback_data, s, this_size);
  66                size -= this_size;
  67                s += this_size;
  68        }
  69}
  70
  71static int xdiff_outf(void *priv_, mmbuffer_t *mb, int nbuf)
  72{
  73        struct xdiff_emit_state *priv = priv_;
  74        int i;
  75
  76        for (i = 0; i < nbuf; i++) {
  77                if (mb[i].ptr[mb[i].size-1] != '\n') {
  78                        /* Incomplete line */
  79                        strbuf_add(&priv->remainder, mb[i].ptr, mb[i].size);
  80                        continue;
  81                }
  82
  83                /* we have a complete line */
  84                if (!priv->remainder.len) {
  85                        consume_one(priv, mb[i].ptr, mb[i].size);
  86                        continue;
  87                }
  88                strbuf_add(&priv->remainder, mb[i].ptr, mb[i].size);
  89                consume_one(priv, priv->remainder.buf, priv->remainder.len);
  90                strbuf_reset(&priv->remainder);
  91        }
  92        if (priv->remainder.len) {
  93                consume_one(priv, priv->remainder.buf, priv->remainder.len);
  94                strbuf_reset(&priv->remainder);
  95        }
  96        return 0;
  97}
  98
  99/*
 100 * Trim down common substring at the end of the buffers,
 101 * but leave at least ctx lines at the end.
 102 */
 103static void trim_common_tail(mmfile_t *a, mmfile_t *b, long ctx)
 104{
 105        const int blk = 1024;
 106        long trimmed = 0, recovered = 0;
 107        char *ap = a->ptr + a->size;
 108        char *bp = b->ptr + b->size;
 109        long smaller = (a->size < b->size) ? a->size : b->size;
 110
 111        if (ctx)
 112                return;
 113
 114        while (blk + trimmed <= smaller && !memcmp(ap - blk, bp - blk, blk)) {
 115                trimmed += blk;
 116                ap -= blk;
 117                bp -= blk;
 118        }
 119
 120        while (recovered < trimmed)
 121                if (ap[recovered++] == '\n')
 122                        break;
 123        a->size -= trimmed - recovered;
 124        b->size -= trimmed - recovered;
 125}
 126
 127int xdi_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp, xdemitconf_t const *xecfg, xdemitcb_t *xecb)
 128{
 129        mmfile_t a = *mf1;
 130        mmfile_t b = *mf2;
 131
 132        trim_common_tail(&a, &b, xecfg->ctxlen);
 133
 134        return xdl_diff(&a, &b, xpp, xecfg, xecb);
 135}
 136
 137int xdi_diff_outf(mmfile_t *mf1, mmfile_t *mf2,
 138                  xdiff_emit_consume_fn fn, void *consume_callback_data,
 139                  xpparam_t const *xpp,
 140                  xdemitconf_t const *xecfg, xdemitcb_t *xecb)
 141{
 142        int ret;
 143        struct xdiff_emit_state state;
 144
 145        memset(&state, 0, sizeof(state));
 146        state.consume = fn;
 147        state.consume_callback_data = consume_callback_data;
 148        xecb->outf = xdiff_outf;
 149        xecb->priv = &state;
 150        strbuf_init(&state.remainder, 0);
 151        ret = xdi_diff(mf1, mf2, xpp, xecfg, xecb);
 152        strbuf_release(&state.remainder);
 153        return ret;
 154}
 155
 156int read_mmfile(mmfile_t *ptr, const char *filename)
 157{
 158        struct stat st;
 159        FILE *f;
 160        size_t sz;
 161
 162        if (stat(filename, &st))
 163                return error("Could not stat %s", filename);
 164        if ((f = fopen(filename, "rb")) == NULL)
 165                return error("Could not open %s", filename);
 166        sz = xsize_t(st.st_size);
 167        ptr->ptr = xmalloc(sz ? sz : 1);
 168        if (sz && fread(ptr->ptr, sz, 1, f) != 1)
 169                return error("Could not read %s", filename);
 170        fclose(f);
 171        ptr->size = sz;
 172        return 0;
 173}
 174
 175#define FIRST_FEW_BYTES 8000
 176int buffer_is_binary(const char *ptr, unsigned long size)
 177{
 178        if (FIRST_FEW_BYTES < size)
 179                size = FIRST_FEW_BYTES;
 180        return !!memchr(ptr, 0, size);
 181}
 182
 183struct ff_regs {
 184        int nr;
 185        struct ff_reg {
 186                regex_t re;
 187                int negate;
 188        } *array;
 189};
 190
 191static long ff_regexp(const char *line, long len,
 192                char *buffer, long buffer_size, void *priv)
 193{
 194        char *line_buffer;
 195        struct ff_regs *regs = priv;
 196        regmatch_t pmatch[2];
 197        int i;
 198        int result = -1;
 199
 200        /* Exclude terminating newline (and cr) from matching */
 201        if (len > 0 && line[len-1] == '\n') {
 202                if (len > 1 && line[len-2] == '\r')
 203                        len -= 2;
 204                else
 205                        len--;
 206        }
 207
 208        line_buffer = xstrndup(line, len); /* make NUL terminated */
 209
 210        /* Exclude terminating newline (and cr) from matching */
 211        if (len > 0 && line[len-1] == '\n') {
 212                if (len > 1 && line[len-2] == '\r')
 213                        len -= 2;
 214                else
 215                        len--;
 216        }
 217
 218        line_buffer = xstrndup(line, len); /* make NUL terminated */
 219
 220        for (i = 0; i < regs->nr; i++) {
 221                struct ff_reg *reg = regs->array + i;
 222                if (!regexec(&reg->re, line_buffer, 2, pmatch, 0)) {
 223                        if (reg->negate)
 224                                goto fail;
 225                        break;
 226                }
 227        }
 228        if (regs->nr <= i)
 229                goto fail;
 230        i = pmatch[1].rm_so >= 0 ? 1 : 0;
 231        line += pmatch[i].rm_so;
 232        result = pmatch[i].rm_eo - pmatch[i].rm_so;
 233        if (result > buffer_size)
 234                result = buffer_size;
 235        else
 236                while (result > 0 && (isspace(line[result - 1])))
 237                        result--;
 238        memcpy(buffer, line, result);
 239 fail:
 240        free(line_buffer);
 241        return result;
 242}
 243
 244void xdiff_set_find_func(xdemitconf_t *xecfg, const char *value, int cflags)
 245{
 246        int i;
 247        struct ff_regs *regs;
 248
 249        xecfg->find_func = ff_regexp;
 250        regs = xecfg->find_func_priv = xmalloc(sizeof(struct ff_regs));
 251        for (i = 0, regs->nr = 1; value[i]; i++)
 252                if (value[i] == '\n')
 253                        regs->nr++;
 254        regs->array = xmalloc(regs->nr * sizeof(struct ff_reg));
 255        for (i = 0; i < regs->nr; i++) {
 256                struct ff_reg *reg = regs->array + i;
 257                const char *ep = strchr(value, '\n'), *expression;
 258                char *buffer = NULL;
 259
 260                reg->negate = (*value == '!');
 261                if (reg->negate && i == regs->nr - 1)
 262                        die("Last expression must not be negated: %s", value);
 263                if (*value == '!')
 264                        value++;
 265                if (ep)
 266                        expression = buffer = xstrndup(value, ep - value);
 267                else
 268                        expression = value;
 269                if (regcomp(&reg->re, expression, cflags))
 270                        die("Invalid regexp to look for hunk header: %s", expression);
 271                free(buffer);
 272                value = ep + 1;
 273        }
 274}
 275
 276int git_xmerge_style = -1;
 277
 278int git_xmerge_config(const char *var, const char *value, void *cb)
 279{
 280        if (!strcasecmp(var, "merge.conflictstyle")) {
 281                if (!value)
 282                        die("'%s' is not a boolean", var);
 283                if (!strcmp(value, "diff3"))
 284                        git_xmerge_style = XDL_MERGE_DIFF3;
 285                else if (!strcmp(value, "merge"))
 286                        git_xmerge_style = 0;
 287                else
 288                        die("unknown style '%s' given for '%s'",
 289                            value, var);
 290                return 0;
 291        }
 292        return git_default_config(var, value, cb);
 293}
 294