diff --git a/xdiff-interface.c b/xdiff-interface.c
index 69a022c134e422abe7c9c1888f59332797ba1eba..61dc5c547019776b971dc89d009f628bbac134fd 100644 (file)
--- a/xdiff-interface.c
+++ b/xdiff-interface.c
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)
{
- return xdl_diff(mf1, mf2, xpp, xecfg, 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 read_mmfile(mmfile_t *ptr, const char *filename)
if ((f = fopen(filename, "rb")) == NULL)
return error("Could not open %s", filename);
sz = xsize_t(st.st_size);
- ptr->ptr = xmalloc(sz);
- if (fread(ptr->ptr, sz, 1, f) != 1)
+ 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;
expression = value;
if (regcomp(®->re, expression, 0))
die("Invalid regexp to look for hunk header: %s", expression);
- if (buffer)
- free(buffer);
+ free(buffer);
value = ep + 1;
}
}