The xdiff library always emits hunk header lines to our callbacks as
formatted strings like "@@ -a,b +c,d @@\n". This is convenient if we're
going to output a diff, but less so if we actually need to compute using
those numbers, which requires re-parsing the line.
In preparation for moving away from this, let's teach xdiff a new
callback function which gets the broken-out hunk information. To help
callers that don't want to use this new callback, if it's NULL we'll
continue to format the hunk header into a string.
Note that this function renames the "outf" callback to "out_line", as
well. This isn't strictly necessary, but helps in two ways:
1. Now that there are two callbacks, it's nice to use more descriptive
names.
2. Many callers did not zero the emit_callback_data struct, and needed
to be modified to set ecb.out_hunk to NULL. By changing the name of
the existing struct member, that guarantees that any new callers
from in-flight topics will break the build and be examined
manually.
Signed-off-by: Jeff King <peff@xxxxxxxx>
---
builtin/merge-tree.c | 3 ++-
builtin/rerere.c | 3 ++-
xdiff-interface.c | 2 +-
xdiff/xdiff.h | 6 +++++-
xdiff/xutils.c | 21 +++++++++++++++++----
5 files changed, 27 insertions(+), 8 deletions(-)
diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c
index 8fc108d305..70f6fc9167 100644
--- a/builtin/merge-tree.c
+++ b/builtin/merge-tree.c
@@ -110,7 +110,8 @@ static void show_diff(struct merge_list *entry)
xpp.flags = 0;
memset(&xecfg, 0, sizeof(xecfg));
xecfg.ctxlen = 3;
- ecb.outf = show_outf;
+ ecb.out_hunk = NULL;
+ ecb.out_line = show_outf;
ecb.priv = NULL;
src.ptr = origin(entry, &size);
diff --git a/builtin/rerere.c b/builtin/rerere.c
index e89ccbc524..d78eeaed32 100644
--- a/builtin/rerere.c
+++ b/builtin/rerere.c
@@ -41,7 +41,8 @@ static int diff_two(const char *file1, const char *label1,
xpp.flags = 0;
memset(&xecfg, 0, sizeof(xecfg));
xecfg.ctxlen = 3;
- ecb.outf = outf;
+ ecb.out_hunk = NULL;
+ ecb.out_line = outf;
ret = xdi_diff(&minus, &plus, &xpp, &xecfg, &ecb);
free(minus.ptr);
diff --git a/xdiff-interface.c b/xdiff-interface.c
index e7af95db86..25c185aff4 100644
--- a/xdiff-interface.c
+++ b/xdiff-interface.c
@@ -152,7 +152,7 @@ int xdi_diff_outf(mmfile_t *mf1, mmfile_t *mf2,
state.consume = fn;
state.consume_callback_data = consume_callback_data;
memset(&ecb, 0, sizeof(ecb));
- ecb.outf = xdiff_outf;
+ ecb.out_line = xdiff_outf;
ecb.priv = &state;
strbuf_init(&state.remainder, 0);
ret = xdi_diff(mf1, mf2, xpp, xecfg, &ecb);
diff --git a/xdiff/xdiff.h b/xdiff/xdiff.h
index 2356da5f78..b158369020 100644
--- a/xdiff/xdiff.h
+++ b/xdiff/xdiff.h
@@ -86,7 +86,11 @@ typedef struct s_xpparam {
typedef struct s_xdemitcb {
void *priv;
- int (*outf)(void *, mmbuffer_t *, int);
+ int (*out_hunk)(void *,
+ long old_begin, long old_nr,
+ long new_begin, long new_nr,
+ const char *func, long funclen);
+ int (*out_line)(void *, mmbuffer_t *, int);
} xdemitcb_t;
typedef long (*find_func_t)(const char *line, long line_len, char *buffer, long buffer_size, void *priv);
diff --git a/xdiff/xutils.c b/xdiff/xutils.c
index 88e5995535..963e1c58b9 100644
--- a/xdiff/xutils.c
+++ b/xdiff/xutils.c
@@ -54,7 +54,7 @@ int xdl_emit_diffrec(char const *rec, long size, char const *pre, long psize,
mb[2].size = strlen(mb[2].ptr);
i++;
}
- if (ecb->outf(ecb->priv, mb, i) < 0) {
+ if (ecb->out_line(ecb->priv, mb, i) < 0) {
return -1;
}
@@ -344,8 +344,9 @@ int xdl_num_out(char *out, long val) {
return str - out;
}
-int xdl_emit_hunk_hdr(long s1, long c1, long s2, long c2,
- const char *func, long funclen, xdemitcb_t *ecb) {
+static int xdl_format_hunk_hdr(long s1, long c1, long s2, long c2,
+ const char *func, long funclen,
+ xdemitcb_t *ecb) {
int nb = 0;
mmbuffer_t mb;
char buf[128];
@@ -387,9 +388,21 @@ int xdl_emit_hunk_hdr(long s1, long c1, long s2, long c2,
mb.ptr = buf;
mb.size = nb;
- if (ecb->outf(ecb->priv, &mb, 1) < 0)
+ if (ecb->out_line(ecb->priv, &mb, 1) < 0)
return -1;
+ return 0;
+}
+int xdl_emit_hunk_hdr(long s1, long c1, long s2, long c2,
+ const char *func, long funclen,
+ xdemitcb_t *ecb) {
+ if (!ecb->out_hunk)
+ return xdl_format_hunk_hdr(s1, c1, s2, c2, func, funclen, ecb);
+ if (ecb->out_hunk(ecb->priv,
+ c1 ? s1 : s1 - 1, c1,
+ c2 ? s2 : s2 - 1, c2,
+ func, funclen) < 0)
+ return -1;
return 0;
}
--
2.19.1.1336.g081079ac04
