Keeping track of the flag bits is proving more trouble than it's
worth. Instead, use a pointer to an options struct like most similar
APIs do.
Callers with no special requests can pass NULL to request the default
options.
Cc: Bert Wesarg <bert.wesarg@xxxxxxxxxxxxxx>
Cc: Avery Pennarun <apenwarr@xxxxxxxxx>
Helped-by: Justin Frankel <justin@xxxxxxxxxx>
Helped-by: Bert Wesarg <bert.wesarg@xxxxxxxxxxxxxx>
Signed-off-by: Jonathan Nieder <jrnieder@xxxxxxxxx>
---
This time, with updated documentation.
Let's avoid the die("BUG: ...") ugliness by using assert().
Documentation/technical/api-merge.txt | 73 +++++++++++++++++++++++---------
builtin/checkout.c | 2 +-
ll-merge.c | 49 +++++++++++++++-------
ll-merge.h | 21 +++-------
merge-file.c | 2 +-
merge-recursive.c | 22 +++++-----
rerere.c | 2 +-
7 files changed, 105 insertions(+), 66 deletions(-)
diff --git a/Documentation/technical/api-merge.txt b/Documentation/technical/api-merge.txt
index a7e050b..9dc1bed 100644
--- a/Documentation/technical/api-merge.txt
+++ b/Documentation/technical/api-merge.txt
@@ -17,6 +17,40 @@ responsible for a few things.
path-specific merge drivers (specified in `.gitattributes`)
into account.
+Data structures
+---------------
+
+* `mmbuffer_t`, `mmfile_t`
+
+These store data usable for use by the xdiff backend, for writing and
+for reading, respectively. See `xdiff/xdiff.h` for the definitions
+and `diff.c` for examples.
+
+* `struct ll_merge_options`
+
+This describes the set of options the calling program wants to affect
+the operation of a low-level (single file) merge. Some options:
+
+`virtual_ancestor`::
+ Behave as though this were part of a merge between common
+ ancestors in a recursive merge.
+ If a helper program is specified by the
+ `[merge "<driver>"] recursive` configuration, it will
+ be used (see linkgit:gitattributes[5]).
+
+`variant`::
+ Resolve local conflicts automatically in favor
+ of one side or the other (as in 'git merge-file'
+ `--ours`/`--theirs`/`--union`). Can be `0`,
+ `XDL_MERGE_FAVOR_OURS`, `XDL_MERGE_FAVOR_THEIRS`, or
+ `XDL_MERGE_FAVOR_UNION`.
+
+`renormalize`::
+ Resmudge and clean the "base", "theirs" and "ours" files
+ before merging. Use this when the merge is likely to have
+ overlapped with a change in smudge/clean or end-of-line
+ normalization rules.
+
Low-level (single file) merge
-----------------------------
@@ -28,15 +62,24 @@ Low-level (single file) merge
`.git/info/attributes` into account. Returns 0 for a
clean merge.
-The caller:
-
-1. allocates an mmbuffer_t variable for the result;
-2. allocates and fills variables with the file's original content
- and two modified versions (using `read_mmfile`, for example);
-3. calls ll_merge();
-4. reads the output from result_buf.ptr and result_buf.size;
-5. releases buffers when finished (free(ancestor.ptr); free(ours.ptr);
- free(theirs.ptr); free(result_buf.ptr);).
+Calling sequence:
+
+* Prepare a `struct ll_merge_options` to record options.
+ If you have no special requests, skip this and pass `NULL`
+ as the `opts` parameter to use the default options.
+
+* Allocate an mmbuffer_t variable for the result.
+
+* Allocate and fill variables with the file's original content
+ and two modified versions (using `read_mmfile`, for example).
+
+* Call `ll_merge()`.
+
+* Read the merged content from `result_buf.ptr` and `result_buf.size`.
+
+* Release buffers when finished. A simple
+ `free(ancestor.ptr); free(ours.ptr); free(theirs.ptr);
+ free(result_buf.ptr);` will do.
If the modifications do not merge cleanly, `ll_merge` will return a
nonzero value and `result_buf` will generally include a description of
@@ -47,18 +90,6 @@ The `ancestor_label`, `our_label`, and `their_label` parameters are
used to label the different sides of a conflict if the merge driver
supports this.
-The `flag` parameter is a bitfield:
-
- - The `LL_OPT_VIRTUAL_ANCESTOR` bit indicates whether this is an
- internal merge to consolidate ancestors for a recursive merge.
-
- - The `LL_OPT_FAVOR_MASK` bits allow local conflicts to be automatically
- resolved in favor of one side or the other (as in 'git merge-file'
- `--ours`/`--theirs`/`--union`).
- They can be populated by `create_ll_flag`, whose argument can be
- `XDL_MERGE_FAVOR_OURS`, `XDL_MERGE_FAVOR_THEIRS`, or
- `XDL_MERGE_FAVOR_UNION`.
-
Everything else
---------------
diff --git a/builtin/checkout.c b/builtin/checkout.c
index 24b67d5..4d36b28 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -155,7 +155,7 @@ static int checkout_merged(int pos, struct checkout *state)
* merge.renormalize set, too
*/
status = ll_merge(&result_buf, path, &ancestor, "base",
- &ours, "ours", &theirs, "theirs", 0);
+ &ours, "ours", &theirs, "theirs", NULL);
free(ancestor.ptr);
free(ours.ptr);
free(theirs.ptr);
diff --git a/ll-merge.c b/ll-merge.c
index 6bb3095..9bd3732 100644
--- a/ll-merge.c
+++ b/ll-merge.c
@@ -18,7 +18,7 @@ typedef int (*ll_merge_fn)(const struct ll_merge_driver *,
mmfile_t *orig, const char *orig_name,
mmfile_t *src1, const char *name1,
mmfile_t *src2, const char *name2,
- int flag,
+ const struct ll_merge_options *opts,
int marker_size);
struct ll_merge_driver {
@@ -39,14 +39,18 @@ static int ll_binary_merge(const struct ll_merge_driver *drv_unused,
mmfile_t *orig, const char *orig_name,
mmfile_t *src1, const char *name1,
mmfile_t *src2, const char *name2,
- int flag, int marker_size)
+ const struct ll_merge_options *opts,
+ int marker_size)
{
+ mmfile_t *stolen;
+ assert(opts);
+
/*
* The tentative merge result is "ours" for the final round,
* or common ancestor for an internal merge. Still return
* "conflicted merge" status.
*/
- mmfile_t *stolen = (flag & LL_OPT_VIRTUAL_ANCESTOR) ? orig : src1;
+ stolen = opts->virtual_ancestor ? orig : src1;
result->ptr = stolen->ptr;
result->size = stolen->size;
@@ -60,9 +64,11 @@ static int ll_xdl_merge(const struct ll_merge_driver *drv_unused,
mmfile_t *orig, const char *orig_name,
mmfile_t *src1, const char *name1,
mmfile_t *src2, const char *name2,
- int flag, int marker_size)
+ const struct ll_merge_options *opts,
+ int marker_size)
{
xmparam_t xmp;
+ assert(opts);
if (buffer_is_binary(orig->ptr, orig->size) ||
buffer_is_binary(src1->ptr, src1->size) ||
@@ -74,12 +80,12 @@ static int ll_xdl_merge(const struct ll_merge_driver *drv_unused,
orig, orig_name,
src1, name1,
src2, name2,
- flag, marker_size);
+ opts, marker_size);
}
memset(&xmp, 0, sizeof(xmp));
xmp.level = XDL_MERGE_ZEALOUS;
- xmp.favor = ll_opt_favor(flag);
+ xmp.favor = opts->variant;
if (git_xmerge_style >= 0)
xmp.style = git_xmerge_style;
if (marker_size > 0)
@@ -96,14 +102,17 @@ static int ll_union_merge(const struct ll_merge_driver *drv_unused,
mmfile_t *orig, const char *orig_name,
mmfile_t *src1, const char *name1,
mmfile_t *src2, const char *name2,
- int flag, int marker_size)
+ const struct ll_merge_options *opts,
+ int marker_size)
{
/* Use union favor */
- flag &= ~LL_OPT_FAVOR_MASK;
- flag |= create_ll_flag(XDL_MERGE_FAVOR_UNION);
+ struct ll_merge_options o;
+ assert(opts);
+ o = *opts;
+ o.variant = XDL_MERGE_FAVOR_UNION;
return ll_xdl_merge(drv_unused, result, path_unused,
orig, NULL, src1, NULL, src2, NULL,
- flag, marker_size);
+ &o, marker_size);
return 0;
}
@@ -136,7 +145,8 @@ static int ll_ext_merge(const struct ll_merge_driver *fn,
mmfile_t *orig, const char *orig_name,
mmfile_t *src1, const char *name1,
mmfile_t *src2, const char *name2,
- int flag, int marker_size)
+ const struct ll_merge_options *opts,
+ int marker_size)
{
char temp[4][50];
struct strbuf cmd = STRBUF_INIT;
@@ -144,6 +154,7 @@ static int ll_ext_merge(const struct ll_merge_driver *fn,
const char *args[] = { NULL, NULL };
int status, fd, i;
struct stat st;
+ assert(opts);
dict[0].placeholder = "O"; dict[0].value = temp[0];
dict[1].placeholder = "A"; dict[1].value = temp[1];
@@ -337,15 +348,21 @@ int ll_merge(mmbuffer_t *result_buf,
mmfile_t *ancestor, const char *ancestor_label,
mmfile_t *ours, const char *our_label,
mmfile_t *theirs, const char *their_label,
- int flag)
+ const struct ll_merge_options *opts)
{
static struct git_attr_check check[2];
const char *ll_driver_name = NULL;
int marker_size = DEFAULT_CONFLICT_MARKER_SIZE;
const struct ll_merge_driver *driver;
- int virtual_ancestor = flag & LL_OPT_VIRTUAL_ANCESTOR;
- if (flag & LL_OPT_RENORMALIZE) {
+ if (!opts) {
+ struct ll_merge_options default_opts = {0};
+ return ll_merge(result_buf, path, ancestor, ancestor_label,
+ ours, our_label, theirs, their_label,
+ &default_opts);
+ }
+
+ if (opts->renormalize) {
normalize_file(ancestor, path);
normalize_file(ours, path);
normalize_file(theirs, path);
@@ -359,11 +376,11 @@ int ll_merge(mmbuffer_t *result_buf,
}
}
driver = find_ll_merge_driver(ll_driver_name);
- if (virtual_ancestor && driver->recursive)
+ if (opts->virtual_ancestor && driver->recursive)
driver = find_ll_merge_driver(driver->recursive);
return driver->fn(driver, result_buf, path, ancestor, ancestor_label,
ours, our_label, theirs, their_label,
- flag, marker_size);
+ opts, marker_size);
}
int ll_merge_marker_size(const char *path)
diff --git a/ll-merge.h b/ll-merge.h
index ff7ca87..4b707f0 100644
--- a/ll-merge.h
+++ b/ll-merge.h
@@ -5,27 +5,18 @@
#ifndef LL_MERGE_H
#define LL_MERGE_H
-#define LL_OPT_VIRTUAL_ANCESTOR (1 << 0)
-#define LL_OPT_FAVOR_MASK ((1 << 1) | (1 << 2))
-#define LL_OPT_FAVOR_SHIFT 1
-#define LL_OPT_RENORMALIZE (1 << 3)
-
-static inline int ll_opt_favor(int flag)
-{
- return (flag & LL_OPT_FAVOR_MASK) >> LL_OPT_FAVOR_SHIFT;
-}
-
-static inline int create_ll_flag(int favor)
-{
- return ((favor << LL_OPT_FAVOR_SHIFT) & LL_OPT_FAVOR_MASK);
-}
+struct ll_merge_options {
+ unsigned virtual_ancestor : 1;
+ unsigned variant : 2; /* favor ours, favor theirs, or union merge */
+ unsigned renormalize : 1;
+};
int ll_merge(mmbuffer_t *result_buf,
const char *path,
mmfile_t *ancestor, const char *ancestor_label,
mmfile_t *ours, const char *our_label,
mmfile_t *theirs, const char *their_label,
- int flag);
+ const struct ll_merge_options *opts);
int ll_merge_marker_size(const char *path);
diff --git a/merge-file.c b/merge-file.c
index db4d0d5..f7f4533 100644
--- a/merge-file.c
+++ b/merge-file.c
@@ -37,7 +37,7 @@ static void *three_way_filemerge(const char *path, mmfile_t *base, mmfile_t *our
* common ancestor.
*/
merge_status = ll_merge(&res, path, base, NULL,
- our, ".our", their, ".their", 0);
+ our, ".our", their, ".their", NULL);
if (merge_status < 0)
return NULL;
diff --git a/merge-recursive.c b/merge-recursive.c
index 44576b7..0e9a29d 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -608,22 +608,25 @@ static int merge_3way(struct merge_options *o,
const char *branch2)
{
mmfile_t orig, src1, src2;
+ struct ll_merge_options ll_opts = {0};
char *base_name, *name1, *name2;
int merge_status;
- int favor;
- if (o->call_depth)
- favor = 0;
- else {
+ ll_opts.renormalize = o->renormalize;
+
+ if (o->call_depth) {
+ ll_opts.virtual_ancestor = 1;
+ ll_opts.variant = 0;
+ } else {
switch (o->recursive_variant) {
case MERGE_RECURSIVE_OURS:
- favor = XDL_MERGE_FAVOR_OURS;
+ ll_opts.variant = XDL_MERGE_FAVOR_OURS;
break;
case MERGE_RECURSIVE_THEIRS:
- favor = XDL_MERGE_FAVOR_THEIRS;
+ ll_opts.variant = XDL_MERGE_FAVOR_THEIRS;
break;
default:
- favor = 0;
+ ll_opts.variant = 0;
break;
}
}
@@ -646,10 +649,7 @@ static int merge_3way(struct merge_options *o,
read_mmblob(&src2, b->sha1);
merge_status = ll_merge(result_buf, a->path, &orig, base_name,
- &src1, name1, &src2, name2,
- ((o->call_depth ? LL_OPT_VIRTUAL_ANCESTOR : 0) |
- (o->renormalize ? LL_OPT_RENORMALIZE : 0) |
- create_ll_flag(favor)));
+ &src1, name1, &src2, name2, &ll_opts);
free(name1);
free(name2);
diff --git a/rerere.c b/rerere.c
index e40af0d..b180218 100644
--- a/rerere.c
+++ b/rerere.c
@@ -325,7 +325,7 @@ static int handle_cache(const char *path, unsigned char *sha1, const char *outpu
*/
ll_merge(&result, path, &mmfile[0], NULL,
&mmfile[1], "ours",
- &mmfile[2], "theirs", 0);
+ &mmfile[2], "theirs", NULL);
for (i = 0; i < 3; i++)
free(mmfile[i].ptr);
--
1.7.2.2
--
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