From a9ed376b158faf82d3685b51d546ccaeda716da3 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Wed, 28 Jun 2006 21:57:12 -0700 Subject: [PATCH] xdiff: generate "anti-diffs" aka what is common to two files This fairly trivial patch adds a new XDL_EMIT_xxx flag to tell libxdiff that we don't want to generate the _diff_ between two files, we want to see the lines that are _common_ to two files. So when you set XDL_EMIT_COMMON, xdl_diff() will do everything exactly like it used to do, but the output records it generates just contain the lines that aren't part of the diff. This is for doing things like generating the common base case for a file that was added in both branches. Signed-off-by: Linus Torvalds Signed-off-by: Junio C Hamano --- xdiff/xdiff.h | 1 + xdiff/xemit.c | 18 ++++++++++++++++++ 2 files changed, 19 insertions(+) diff --git a/xdiff/xdiff.h b/xdiff/xdiff.h index 2ce10b4c0..c9f817818 100644 --- a/xdiff/xdiff.h +++ b/xdiff/xdiff.h @@ -39,6 +39,7 @@ extern "C" { #define XDL_PATCH_IGNOREBSPACE (1 << 8) #define XDL_EMIT_FUNCNAMES (1 << 0) +#define XDL_EMIT_COMMON (1 << 1) #define XDL_MMB_READONLY (1 << 0) diff --git a/xdiff/xemit.c b/xdiff/xemit.c index ad5bfb191..714c56354 100644 --- a/xdiff/xemit.c +++ b/xdiff/xemit.c @@ -100,6 +100,21 @@ static void xdl_find_func(xdfile_t *xf, long i, char *buf, long sz, long *ll) { } +int xdl_emit_common(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb, + xdemitconf_t const *xecfg) { + xdfile_t *xdf = &xe->xdf1; + const char *rchg = xdf->rchg; + long ix; + + for (ix = 0; ix < xdf->nrec; ix++) { + if (rchg[ix]) + continue; + if (xdl_emit_record(xdf, ix, "", ecb)) + return -1; + } + return 0; +} + int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb, xdemitconf_t const *xecfg) { long s1, s2, e1, e2, lctx; @@ -107,6 +122,9 @@ int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb, char funcbuf[40]; long funclen = 0; + if (xecfg->flags & XDL_EMIT_COMMON) + return xdl_emit_common(xe, xscr, ecb, xecfg); + for (xch = xche = xscr; xch; xch = xche->next) { xche = xdl_get_hunk(xch, xecfg); -- 2.30.2