gitweb: unify boolean feature subroutines
[gitweb.git] / xdiff-interface.c
index 0a66ded9533009a8efb840db5377f0abf5fccb1b..d782f06d9916bdde33dc3f7312f9eac4e14ef3a1 100644 (file)
@@ -1,5 +1,61 @@
 #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)
 {
@@ -9,13 +65,13 @@ static void consume_one(void *priv_, char *s, unsigned long size)
                unsigned long this_size;
                ep = memchr(s, '\n', size);
                this_size = (ep == NULL) ? size : (ep - s + 1);
-               priv->consume(priv, s, this_size);
+               priv->consume(priv->consume_callback_data, s, this_size);
                size -= this_size;
                s += this_size;
        }
 }
 
-int xdiff_outf(void *priv_, mmbuffer_t *mb, int nbuf)
+static int xdiff_outf(void *priv_, mmbuffer_t *mb, int nbuf)
 {
        struct xdiff_emit_state *priv = priv_;
        int i;
@@ -23,36 +79,252 @@ int xdiff_outf(void *priv_, mmbuffer_t *mb, int nbuf)
        for (i = 0; i < nbuf; i++) {
                if (mb[i].ptr[mb[i].size-1] != '\n') {
                        /* Incomplete line */
-                       priv->remainder = realloc(priv->remainder,
-                                                 priv->remainder_size +
-                                                 mb[i].size);
-                       memcpy(priv->remainder + priv->remainder_size,
-                              mb[i].ptr, mb[i].size);
-                       priv->remainder_size += mb[i].size;
+                       strbuf_add(&priv->remainder, mb[i].ptr, mb[i].size);
                        continue;
                }
 
                /* we have a complete line */
-               if (!priv->remainder) {
+               if (!priv->remainder.len) {
                        consume_one(priv, mb[i].ptr, mb[i].size);
                        continue;
                }
-               priv->remainder = realloc(priv->remainder,
-                                         priv->remainder_size +
-                                         mb[i].size);
-               memcpy(priv->remainder + priv->remainder_size,
-                      mb[i].ptr, mb[i].size);
-               consume_one(priv, priv->remainder,
-                           priv->remainder_size + mb[i].size);
-               free(priv->remainder);
-               priv->remainder = NULL;
-               priv->remainder_size = 0;
-       }
-       if (priv->remainder) {
-               consume_one(priv, priv->remainder, priv->remainder_size);
-               free(priv->remainder);
-               priv->remainder = NULL;
-               priv->remainder_size = 0;
+               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(&reg->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(&reg->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);
+}