diff options
Diffstat (limited to 'xdiff-interface.c')
| -rw-r--r-- | xdiff-interface.c | 330 |
1 files changed, 330 insertions, 0 deletions
diff --git a/xdiff-interface.c b/xdiff-interface.c new file mode 100644 index 000000000..d782f06d9 --- /dev/null +++ b/xdiff-interface.c @@ -0,0 +1,330 @@ +#include "cache.h" +#include "xdiff-interface.h" +#include "xdiff/xtypes.h" +#include "xdiff/xdiffi.h" +#include "xdiff/xemit.h" +#include "xdiff/xmacros.h" + +struct xdiff_emit_state { + xdiff_emit_consume_fn consume; + void *consume_callback_data; + struct strbuf remainder; +}; + +static int parse_num(char **cp_p, int *num_p) +{ + char *cp = *cp_p; + int num = 0; + int read_some; + + while ('0' <= *cp && *cp <= '9') + num = num * 10 + *cp++ - '0'; + if (!(read_some = cp - *cp_p)) + return -1; + *cp_p = cp; + *num_p = num; + return 0; +} + +int parse_hunk_header(char *line, int len, + int *ob, int *on, + int *nb, int *nn) +{ + char *cp; + cp = line + 4; + if (parse_num(&cp, ob)) { + bad_line: + return error("malformed diff output: %s", line); + } + if (*cp == ',') { + cp++; + if (parse_num(&cp, on)) + goto bad_line; + } + else + *on = 1; + if (*cp++ != ' ' || *cp++ != '+') + goto bad_line; + if (parse_num(&cp, nb)) + goto bad_line; + if (*cp == ',') { + cp++; + if (parse_num(&cp, nn)) + goto bad_line; + } + else + *nn = 1; + return -!!memcmp(cp, " @@", 3); +} + +static void consume_one(void *priv_, char *s, unsigned long size) +{ + struct xdiff_emit_state *priv = priv_; + char *ep; + while (size) { + unsigned long this_size; + ep = memchr(s, '\n', size); + this_size = (ep == NULL) ? size : (ep - s + 1); + priv->consume(priv->consume_callback_data, s, this_size); + size -= this_size; + s += this_size; + } +} + +static int xdiff_outf(void *priv_, mmbuffer_t *mb, int nbuf) +{ + struct xdiff_emit_state *priv = priv_; + int i; + + for (i = 0; i < nbuf; i++) { + if (mb[i].ptr[mb[i].size-1] != '\n') { + /* Incomplete line */ + strbuf_add(&priv->remainder, mb[i].ptr, mb[i].size); + continue; + } + + /* we have a complete line */ + if (!priv->remainder.len) { + consume_one(priv, mb[i].ptr, mb[i].size); + continue; + } + strbuf_add(&priv->remainder, mb[i].ptr, mb[i].size); + consume_one(priv, priv->remainder.buf, priv->remainder.len); + strbuf_reset(&priv->remainder); + } + if (priv->remainder.len) { + consume_one(priv, priv->remainder.buf, priv->remainder.len); + strbuf_reset(&priv->remainder); + } + return 0; +} + +/* + * Trim down common substring at the end of the buffers, + * but leave at least ctx lines at the end. + */ +static void trim_common_tail(mmfile_t *a, mmfile_t *b, long ctx) +{ + const int blk = 1024; + long trimmed = 0, recovered = 0; + char *ap = a->ptr + a->size; + char *bp = b->ptr + b->size; + long smaller = (a->size < b->size) ? a->size : b->size; + + if (ctx) + return; + + while (blk + trimmed <= smaller && !memcmp(ap - blk, bp - blk, blk)) { + trimmed += blk; + ap -= blk; + bp -= blk; + } + + while (recovered < trimmed) + if (ap[recovered++] == '\n') + break; + a->size -= trimmed - recovered; + b->size -= trimmed - recovered; +} + +int xdi_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp, xdemitconf_t const *xecfg, xdemitcb_t *xecb) +{ + mmfile_t a = *mf1; + mmfile_t b = *mf2; + + trim_common_tail(&a, &b, xecfg->ctxlen); + + return xdl_diff(&a, &b, xpp, xecfg, xecb); +} + +int xdi_diff_outf(mmfile_t *mf1, mmfile_t *mf2, + xdiff_emit_consume_fn fn, void *consume_callback_data, + xpparam_t const *xpp, + xdemitconf_t const *xecfg, xdemitcb_t *xecb) +{ + int ret; + struct xdiff_emit_state state; + + memset(&state, 0, sizeof(state)); + state.consume = fn; + state.consume_callback_data = consume_callback_data; + xecb->outf = xdiff_outf; + xecb->priv = &state; + strbuf_init(&state.remainder, 0); + ret = xdi_diff(mf1, mf2, xpp, xecfg, xecb); + strbuf_release(&state.remainder); + return ret; +} + +struct xdiff_emit_hunk_state { + xdiff_emit_hunk_consume_fn consume; + void *consume_callback_data; +}; + +static int process_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb, + xdemitconf_t const *xecfg) +{ + long s1, s2, same, p_next, t_next; + xdchange_t *xch, *xche; + struct xdiff_emit_hunk_state *state = ecb->priv; + xdiff_emit_hunk_consume_fn fn = state->consume; + void *consume_callback_data = state->consume_callback_data; + + for (xch = xscr; xch; xch = xche->next) { + xche = xdl_get_hunk(xch, xecfg); + + s1 = XDL_MAX(xch->i1 - xecfg->ctxlen, 0); + s2 = XDL_MAX(xch->i2 - xecfg->ctxlen, 0); + same = s2 + XDL_MAX(xch->i1 - s1, 0); + p_next = xche->i1 + xche->chg1; + t_next = xche->i2 + xche->chg2; + + fn(consume_callback_data, same, p_next, t_next); + } + return 0; +} + +int xdi_diff_hunks(mmfile_t *mf1, mmfile_t *mf2, + xdiff_emit_hunk_consume_fn fn, void *consume_callback_data, + xpparam_t const *xpp, xdemitconf_t *xecfg) +{ + struct xdiff_emit_hunk_state state; + xdemitcb_t ecb; + + memset(&state, 0, sizeof(state)); + memset(&ecb, 0, sizeof(ecb)); + state.consume = fn; + state.consume_callback_data = consume_callback_data; + xecfg->emit_func = (void (*)())process_diff; + ecb.priv = &state; + return xdi_diff(mf1, mf2, xpp, xecfg, &ecb); +} + +int read_mmfile(mmfile_t *ptr, const char *filename) +{ + struct stat st; + FILE *f; + size_t sz; + + if (stat(filename, &st)) + return error("Could not stat %s", filename); + if ((f = fopen(filename, "rb")) == NULL) + return error("Could not open %s", filename); + sz = xsize_t(st.st_size); + ptr->ptr = xmalloc(sz ? sz : 1); + if (sz && fread(ptr->ptr, sz, 1, f) != 1) + return error("Could not read %s", filename); + fclose(f); + ptr->size = sz; + return 0; +} + +#define FIRST_FEW_BYTES 8000 +int buffer_is_binary(const char *ptr, unsigned long size) +{ + if (FIRST_FEW_BYTES < size) + size = FIRST_FEW_BYTES; + return !!memchr(ptr, 0, size); +} + +struct ff_regs { + int nr; + struct ff_reg { + regex_t re; + int negate; + } *array; +}; + +static long ff_regexp(const char *line, long len, + char *buffer, long buffer_size, void *priv) +{ + char *line_buffer; + struct ff_regs *regs = priv; + regmatch_t pmatch[2]; + int i; + int result = -1; + + /* Exclude terminating newline (and cr) from matching */ + if (len > 0 && line[len-1] == '\n') { + if (len > 1 && line[len-2] == '\r') + len -= 2; + else + len--; + } + + line_buffer = xstrndup(line, len); /* make NUL terminated */ + + for (i = 0; i < regs->nr; i++) { + struct ff_reg *reg = regs->array + i; + if (!regexec(®->re, line_buffer, 2, pmatch, 0)) { + if (reg->negate) + goto fail; + break; + } + } + if (regs->nr <= i) + goto fail; + i = pmatch[1].rm_so >= 0 ? 1 : 0; + line += pmatch[i].rm_so; + result = pmatch[i].rm_eo - pmatch[i].rm_so; + if (result > buffer_size) + result = buffer_size; + else + while (result > 0 && (isspace(line[result - 1]))) + result--; + memcpy(buffer, line, result); + fail: + free(line_buffer); + return result; +} + +void xdiff_set_find_func(xdemitconf_t *xecfg, const char *value, int cflags) +{ + int i; + struct ff_regs *regs; + + xecfg->find_func = ff_regexp; + regs = xecfg->find_func_priv = xmalloc(sizeof(struct ff_regs)); + for (i = 0, regs->nr = 1; value[i]; i++) + if (value[i] == '\n') + regs->nr++; + regs->array = xmalloc(regs->nr * sizeof(struct ff_reg)); + for (i = 0; i < regs->nr; i++) { + struct ff_reg *reg = regs->array + i; + const char *ep = strchr(value, '\n'), *expression; + char *buffer = NULL; + + reg->negate = (*value == '!'); + if (reg->negate && i == regs->nr - 1) + die("Last expression must not be negated: %s", value); + if (*value == '!') + value++; + if (ep) + expression = buffer = xstrndup(value, ep - value); + else + expression = value; + if (regcomp(®->re, expression, cflags)) + die("Invalid regexp to look for hunk header: %s", expression); + free(buffer); + value = ep + 1; + } +} + +int git_xmerge_style = -1; + +int git_xmerge_config(const char *var, const char *value, void *cb) +{ + if (!strcasecmp(var, "merge.conflictstyle")) { + if (!value) + die("'%s' is not a boolean", var); + if (!strcmp(value, "diff3")) + git_xmerge_style = XDL_MERGE_DIFF3; + else if (!strcmp(value, "merge")) + git_xmerge_style = 0; + else + die("unknown style '%s' given for '%s'", + value, var); + return 0; + } + return git_default_config(var, value, cb); +} |