/*
* Copyright (C) the libgit2 contributors. All rights reserved.
*
* This file is part of libgit2, distributed under the GNU GPL v2 with
* a Linking Exception. For full terms see the included COPYING file.
*/
#include "common.h"
#include "repository.h"
#include "posix.h"
#include "futils.h"
#include "index.h"
#include "diff_xdiff.h"
#include "merge.h"
#include "git2/repository.h"
#include "git2/object.h"
#include "git2/index.h"
#include "git2/merge.h"
#include "xdiff/xdiff.h"
/* only examine the first 8000 bytes for binaryness.
* https://github.com/git/git/blob/77bd3ea9f54f1584147b594abc04c26ca516d987/xdiff-interface.c#L197
*/
#define GIT_MERGE_FILE_BINARY_SIZE 8000
#define GIT_MERGE_FILE_SIDE_EXISTS(X) ((X)->mode != 0)
static int merge_file_input_from_index(
git_merge_file_input *input_out,
git_odb_object **odb_object_out,
git_odb *odb,
const git_index_entry *entry)
{
int error = 0;
GIT_ASSERT_ARG(input_out);
GIT_ASSERT_ARG(odb_object_out);
GIT_ASSERT_ARG(odb);
GIT_ASSERT_ARG(entry);
if ((error = git_odb_read(odb_object_out, odb, &entry->id)) < 0)
goto done;
input_out->path = entry->path;
input_out->mode = entry->mode;
input_out->ptr = (char *)git_odb_object_data(*odb_object_out);
input_out->size = git_odb_object_size(*odb_object_out);
done:
return error;
}
static void merge_file_normalize_opts(
git_merge_file_options *out,
const git_merge_file_options *given_opts)
{
if (given_opts)
memcpy(out, given_opts, sizeof(git_merge_file_options));
else {
git_merge_file_options default_opts = GIT_MERGE_FILE_OPTIONS_INIT;
memcpy(out, &default_opts, sizeof(git_merge_file_options));
}
}
static int merge_file__xdiff(
git_merge_file_result *out,
const git_merge_file_input *ancestor,
const git_merge_file_input *ours,
const git_merge_file_input *theirs,
const git_merge_file_options *given_opts)
{
xmparam_t xmparam;
mmfile_t ancestor_mmfile = {0}, our_mmfile = {0}, their_mmfile = {0};
mmbuffer_t mmbuffer;
git_merge_file_options options = GIT_MERGE_FILE_OPTIONS_INIT;
const char *path;
int xdl_result;
int error = 0;
memset(out, 0x0, sizeof(git_merge_file_result));
merge_file_normalize_opts(&options, given_opts);
memset(&xmparam, 0x0, sizeof(xmparam_t));
if (ancestor) {
xmparam.ancestor = (options.ancestor_label) ?
options.ancestor_label : ancestor->path;
ancestor_mmfile.ptr = (char *)ancestor->ptr;
ancestor_mmfile.size = ancestor->size;
}
xmparam.file1 = (options.our_label) ?
options.our_label : ours->path;
our_mmfile.ptr = (char *)ours->ptr;
our_mmfile.size = ours->size;
xmparam.file2 = (options.their_label) ?
options.their_label : theirs->path;
their_mmfile.ptr = (char *)theirs->ptr;
their_mmfile.size = theirs->size;
if (options.favor == GIT_MERGE_FILE_FAVOR_OURS)
xmparam.favor = XDL_MERGE_FAVOR_OURS;
else if (options.favor == GIT_MERGE_FILE_FAVOR_THEIRS)
xmparam.favor = XDL_MERGE_FAVOR_THEIRS;
else if (options.favor == GIT_MERGE_FILE_FAVOR_UNION)
xmparam.favor = XDL_MERGE_FAVOR_UNION;
xmparam.level = (options.flags & GIT_MERGE_FILE_SIMPLIFY_ALNUM) ?
XDL_MERGE_ZEALOUS_ALNUM : XDL_MERGE_ZEALOUS;
if (options.flags & GIT_MERGE_FILE_STYLE_DIFF3)
xmparam.style = XDL_MERGE_DIFF3;
if (options.flags & GIT_MERGE_FILE_IGNORE_WHITESPACE)
xmparam.xpp.flags |= XDF_IGNORE_WHITESPACE;
if (options.flags & GIT_MERGE_FILE_IGNORE_WHITESPACE_CHANGE)
xmparam.xpp.flags |= XDF_IGNORE_WHITESPACE_CHANGE;
if (options.flags & GIT_MERGE_FILE_IGNORE_WHITESPACE_EOL)
xmparam.xpp.flags |= XDF_IGNORE_WHITESPACE_AT_EOL;
if (options.flags & GIT_MERGE_FILE_DIFF_PATIENCE)
xmparam.xpp.flags |= XDF_PATIENCE_DIFF;
if (options.flags & GIT_MERGE_FILE_DIFF_MINIMAL)
xmparam.xpp.flags |= XDF_NEED_MINIMAL;
xmparam.marker_size = options.marker_size;
if ((xdl_result = xdl_merge(&ancestor_mmfile, &our_mmfile,
&their_mmfile, &xmparam, &mmbuffer)) < 0) {
git_error_set(GIT_ERROR_MERGE, "failed to merge files");
error = -1;
goto done;
}
path = git_merge_file__best_path(
ancestor ? ancestor->path : NULL,
ours->path,
theirs->path);
if (path != NULL && (out->path = git__strdup(path)) == NULL) {
error = -1;
goto done;
}
out->automergeable = (xdl_result == 0);
out->ptr = (const char *)mmbuffer.ptr;
out->len = mmbuffer.size;
out->mode = git_merge_file__best_mode(
ancestor ? ancestor->mode : 0,
ours->mode,
theirs->mode);
done:
if (error < 0)
git_merge_file_result_free(out);
return error;
}
static bool merge_file__is_binary(const git_merge_file_input *file)
{
size_t len = file ? file->size : 0;
if (len > GIT_XDIFF_MAX_SIZE)
return true;
if (len > GIT_MERGE_FILE_BINARY_SIZE)
len = GIT_MERGE_FILE_BINARY_SIZE;
return len ? (memchr(file->ptr, 0, len) != NULL) : false;
}
static int merge_file__binary(
git_merge_file_result *out,
const git_merge_file_input *ours,
const git_merge_file_input *theirs,
const git_merge_file_options *given_opts)
{
const git_merge_file_input *favored = NULL;
memset(out, 0x0, sizeof(git_merge_file_result));
if (given_opts && given_opts->favor == GIT_MERGE_FILE_FAVOR_OURS)
favored = ours;
else if (given_opts && given_opts->favor == GIT_MERGE_FILE_FAVOR_THEIRS)
favored = theirs;
else
goto done;
if ((out->path = git__strdup(favored->path)) == NULL ||
(out->ptr = git__malloc(favored->size)) == NULL)
goto done;
memcpy((char *)out->ptr, favored->ptr, favored->size);
out->len = favored->size;
out->mode = favored->mode;
out->automergeable = 1;
done:
return 0;
}
static int merge_file__from_inputs(
git_merge_file_result *out,
const git_merge_file_input *ancestor,
const git_merge_file_input *ours,
const git_merge_file_input *theirs,
const git_merge_file_options *given_opts)
{
if (merge_file__is_binary(ancestor) ||
merge_file__is_binary(ours) ||
merge_file__is_binary(theirs))
return merge_file__binary(out, ours, theirs, given_opts);
return merge_file__xdiff(out, ancestor, ours, theirs, given_opts);
}
static git_merge_file_input *git_merge_file__normalize_inputs(
git_merge_file_input *out,
const git_merge_file_input *given)
{
memcpy(out, given, sizeof(git_merge_file_input));
if (!out->path)
out->path = "file.txt";
if (!out->mode)
out->mode = 0100644;
return out;
}
int git_merge_file(
git_merge_file_result *out,
const git_merge_file_input *ancestor,
const git_merge_file_input *ours,
const git_merge_file_input *theirs,
const git_merge_file_options *options)
{
git_merge_file_input inputs[3] = { {0} };
GIT_ASSERT_ARG(out);
GIT_ASSERT_ARG(ours);
GIT_ASSERT_ARG(theirs);
memset(out, 0x0, sizeof(git_merge_file_result));
if (ancestor)
ancestor = git_merge_file__normalize_inputs(&inputs[0], ancestor);
ours = git_merge_file__normalize_inputs(&inputs[1], ours);
theirs = git_merge_file__normalize_inputs(&inputs[2], theirs);
return merge_file__from_inputs(out, ancestor, ours, theirs, options);
}
int git_merge_file_from_index(
git_merge_file_result *out,
git_repository *repo,
const git_index_entry *ancestor,
const git_index_entry *ours,
const git_index_entry *theirs,
const git_merge_file_options *options)
{
git_merge_file_input *ancestor_ptr = NULL,
ancestor_input = {0}, our_input = {0}, their_input = {0};
git_odb *odb = NULL;
git_odb_object *odb_object[3] = { 0 };
int error = 0;
GIT_ASSERT_ARG(out);
GIT_ASSERT_ARG(repo);
GIT_ASSERT_ARG(ours);
GIT_ASSERT_ARG(theirs);
memset(out, 0x0, sizeof(git_merge_file_result));
if ((error = git_repository_odb(&odb, repo)) < 0)
goto done;
if (ancestor) {
if ((error = merge_file_input_from_index(
&ancestor_input, &odb_object[0], odb, ancestor)) < 0)
goto done;
ancestor_ptr = &ancestor_input;
}
if ((error = merge_file_input_from_index(&our_input, &odb_object[1], odb, ours)) < 0 ||
(error = merge_file_input_from_index(&their_input, &odb_object[2], odb, theirs)) < 0)
goto done;
error = merge_file__from_inputs(out,
ancestor_ptr, &our_input, &their_input, options);
done:
git_odb_object_free(odb_object[0]);
git_odb_object_free(odb_object[1]);
git_odb_object_free(odb_object[2]);
git_odb_free(odb);
return error;
}
void git_merge_file_result_free(git_merge_file_result *result)
{
if (result == NULL)
return;
git__free((char *)result->path);
git__free((char *)result->ptr);
}
