apply.c 20.8 KB
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/*
 * 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.
 */

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#include "apply.h"

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#include <assert.h>

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#include "git2/apply.h"
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#include "git2/patch.h"
#include "git2/filter.h"
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#include "git2/blob.h"
#include "git2/index.h"
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#include "git2/checkout.h"
#include "git2/repository.h"
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#include "array.h"
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#include "patch.h"
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#include "fileops.h"
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#include "delta.h"
#include "zstream.h"
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#include "reader.h"
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#include "index.h"
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#define apply_err(...) \
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	( git_error_set(GIT_ERROR_PATCH, __VA_ARGS__), GIT_EAPPLYFAIL )
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typedef struct {
	/* The lines that we allocate ourself are allocated out of the pool.
	 * (Lines may have been allocated out of the diff.)
	 */
	git_pool pool;
	git_vector lines;
} patch_image;

static void patch_line_init(
	git_diff_line *out,
	const char *in,
	size_t in_len,
	size_t in_offset)
{
	out->content = in;
	out->content_len = in_len;
	out->content_offset = in_offset;
}

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#define PATCH_IMAGE_INIT { GIT_POOL_INIT, GIT_VECTOR_INIT }
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static int patch_image_init_fromstr(
	patch_image *out, const char *in, size_t in_len)
{
	git_diff_line *line;
	const char *start, *end;

	memset(out, 0x0, sizeof(patch_image));

	git_pool_init(&out->pool, sizeof(git_diff_line));

	for (start = in; start < in + in_len; start = end) {
		end = memchr(start, '\n', in_len);

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		if (end == NULL)
			end = in + in_len;

		else if (end < in + in_len)
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			end++;

		line = git_pool_mallocz(&out->pool, 1);
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		GIT_ERROR_CHECK_ALLOC(line);
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		if (git_vector_insert(&out->lines, line) < 0)
			return -1;

		patch_line_init(line, start, (end - start), (start - in));
	}

	return 0;
}

static void patch_image_free(patch_image *image)
{
	if (image == NULL)
		return;

	git_pool_clear(&image->pool);
	git_vector_free(&image->lines);
}

static bool match_hunk(
	patch_image *image,
	patch_image *preimage,
	size_t linenum)
{
	bool match = 0;
	size_t i;

	/* Ensure this hunk is within the image boundaries. */
	if (git_vector_length(&preimage->lines) + linenum >
		git_vector_length(&image->lines))
		return 0;

	match = 1;

	/* Check exact match. */
	for (i = 0; i < git_vector_length(&preimage->lines); i++) {
		git_diff_line *preimage_line = git_vector_get(&preimage->lines, i);
		git_diff_line *image_line = git_vector_get(&image->lines, linenum + i);

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		if (preimage_line->content_len != image_line->content_len ||
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			memcmp(preimage_line->content, image_line->content, image_line->content_len) != 0) {
			match = 0;
			break;
		}
	}

	return match;
}

static bool find_hunk_linenum(
	size_t *out,
	patch_image *image,
	patch_image *preimage,
	size_t linenum)
{
	size_t max = git_vector_length(&image->lines);
	bool match;

	if (linenum > max)
		linenum = max;

	match = match_hunk(image, preimage, linenum);

	*out = linenum;
	return match;
}

static int update_hunk(
	patch_image *image,
	unsigned int linenum,
	patch_image *preimage,
	patch_image *postimage)
{
	size_t postlen = git_vector_length(&postimage->lines);
	size_t prelen = git_vector_length(&preimage->lines);
	size_t i;
	int error = 0;

	if (postlen > prelen)
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		error = git_vector_insert_null(
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			&image->lines, linenum, (postlen - prelen));
	else if (prelen > postlen)
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		error = git_vector_remove_range(
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			&image->lines, linenum, (prelen - postlen));

	if (error) {
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		git_error_set_oom();
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		return -1;
	}

	for (i = 0; i < git_vector_length(&postimage->lines); i++) {
		image->lines.contents[linenum + i] =
			git_vector_get(&postimage->lines, i);
	}

	return 0;
}

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typedef struct {
	git_apply_options opts;
	size_t skipped_new_lines;
	size_t skipped_old_lines;
} apply_hunks_ctx;

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static int apply_hunk(
	patch_image *image,
	git_patch *patch,
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	git_patch_hunk *hunk,
	apply_hunks_ctx *ctx)
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{
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	patch_image preimage = PATCH_IMAGE_INIT, postimage = PATCH_IMAGE_INIT;
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	size_t line_num, i;
	int error = 0;

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	if (ctx->opts.hunk_cb) {
		error = ctx->opts.hunk_cb(&hunk->hunk, ctx->opts.payload);

		if (error) {
			if (error > 0) {
				ctx->skipped_new_lines += hunk->hunk.new_lines;
				ctx->skipped_old_lines += hunk->hunk.old_lines;
				error = 0;
			}

			goto done;
		}
	}

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	for (i = 0; i < hunk->line_count; i++) {
		size_t linenum = hunk->line_start + i;
		git_diff_line *line = git_array_get(patch->lines, linenum);

		if (!line) {
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			error = apply_err("preimage does not contain line %"PRIuZ, linenum);
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			goto done;
		}

		if (line->origin == GIT_DIFF_LINE_CONTEXT ||
			line->origin == GIT_DIFF_LINE_DELETION) {
			if ((error = git_vector_insert(&preimage.lines, line)) < 0)
				goto done;
		}

		if (line->origin == GIT_DIFF_LINE_CONTEXT ||
			line->origin == GIT_DIFF_LINE_ADDITION) {
			if ((error = git_vector_insert(&postimage.lines, line)) < 0)
				goto done;
		}
	}

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	if (hunk->hunk.new_start) {
		line_num = hunk->hunk.new_start -
			ctx->skipped_new_lines +
			ctx->skipped_old_lines -
			1;
	} else {
		line_num = 0;
	}
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	if (!find_hunk_linenum(&line_num, image, &preimage, line_num)) {
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		error = apply_err("hunk at line %d did not apply",
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			hunk->hunk.new_start);
		goto done;
	}

	error = update_hunk(image, line_num, &preimage, &postimage);

done:
	patch_image_free(&preimage);
	patch_image_free(&postimage);

	return error;
}

static int apply_hunks(
	git_buf *out,
	const char *source,
	size_t source_len,
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	git_patch *patch,
	apply_hunks_ctx *ctx)
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{
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	git_patch_hunk *hunk;
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	git_diff_line *line;
	patch_image image;
	size_t i;
	int error = 0;

	if ((error = patch_image_init_fromstr(&image, source, source_len)) < 0)
		goto done;

	git_array_foreach(patch->hunks, i, hunk) {
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		if ((error = apply_hunk(&image, patch, hunk, ctx)) < 0)
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			goto done;
	}

	git_vector_foreach(&image.lines, i, line)
		git_buf_put(out, line->content, line->content_len);

done:
	patch_image_free(&image);

	return error;
}

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static int apply_binary_delta(
	git_buf *out,
	const char *source,
	size_t source_len,
	git_diff_binary_file *binary_file)
{
	git_buf inflated = GIT_BUF_INIT;
	int error = 0;

	/* no diff means identical contents */
	if (binary_file->datalen == 0)
		return git_buf_put(out, source, source_len);

	error = git_zstream_inflatebuf(&inflated,
		binary_file->data, binary_file->datalen);

	if (!error && inflated.size != binary_file->inflatedlen) {
		error = apply_err("inflated delta does not match expected length");
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		git_buf_dispose(out);
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	}

	if (error < 0)
		goto done;

	if (binary_file->type == GIT_DIFF_BINARY_DELTA) {
		void *data;
		size_t data_len;

		error = git_delta_apply(&data, &data_len, (void *)source, source_len,
			(void *)inflated.ptr, inflated.size);

		out->ptr = data;
		out->size = data_len;
		out->asize = data_len;
	}
	else if (binary_file->type == GIT_DIFF_BINARY_LITERAL) {
		git_buf_swap(out, &inflated);
	}
	else {
		error = apply_err("unknown binary delta type");
		goto done;
	}

done:
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	git_buf_dispose(&inflated);
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	return error;
}

static int apply_binary(
	git_buf *out,
	const char *source,
	size_t source_len,
	git_patch *patch)
{
	git_buf reverse = GIT_BUF_INIT;
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	int error = 0;

	if (!patch->binary.contains_data) {
		error = apply_err("patch does not contain binary data");
		goto done;
	}

	if (!patch->binary.old_file.datalen && !patch->binary.new_file.datalen)
		goto done;
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	/* first, apply the new_file delta to the given source */
	if ((error = apply_binary_delta(out, source, source_len,
			&patch->binary.new_file)) < 0)
		goto done;

	/* second, apply the old_file delta to sanity check the result */
	if ((error = apply_binary_delta(&reverse, out->ptr, out->size,
			&patch->binary.old_file)) < 0)
		goto done;

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	/* Verify that the resulting file with the reverse patch applied matches the source file */
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	if (source_len != reverse.size ||
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		(source_len && memcmp(source, reverse.ptr, source_len) != 0)) {
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		error = apply_err("binary patch did not apply cleanly");
		goto done;
	}

done:
	if (error < 0)
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		git_buf_dispose(out);
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	git_buf_dispose(&reverse);
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	return error;
}

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int git_apply__patch(
	git_buf *contents_out,
	char **filename_out,
	unsigned int *mode_out,
	const char *source,
	size_t source_len,
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	git_patch *patch,
	const git_apply_options *given_opts)
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{
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	apply_hunks_ctx ctx = { GIT_APPLY_OPTIONS_INIT };
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	char *filename = NULL;
	unsigned int mode = 0;
	int error = 0;

	assert(contents_out && filename_out && mode_out && (source || !source_len) && patch);

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	if (given_opts)
		memcpy(&ctx.opts, given_opts, sizeof(git_apply_options));

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	*filename_out = NULL;
	*mode_out = 0;

	if (patch->delta->status != GIT_DELTA_DELETED) {
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		const git_diff_file *newfile = &patch->delta->new_file;
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		filename = git__strdup(newfile->path);
		mode = newfile->mode ?
			newfile->mode : GIT_FILEMODE_BLOB;
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	}

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	if (patch->delta->flags & GIT_DIFF_FLAG_BINARY)
		error = apply_binary(contents_out, source, source_len, patch);
	else if (patch->hunks.size)
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		error = apply_hunks(contents_out, source, source_len, patch, &ctx);
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	else
		error = git_buf_put(contents_out, source, source_len);

	if (error)
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		goto done;

	if (patch->delta->status == GIT_DELTA_DELETED &&
		git_buf_len(contents_out) > 0) {
		error = apply_err("removal patch leaves file contents");
		goto done;
	}

	*filename_out = filename;
	*mode_out = mode;

done:
	if (error < 0)
		git__free(filename);

	return error;
}
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static int apply_one(
	git_repository *repo,
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	git_reader *preimage_reader,
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	git_index *preimage,
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	git_reader *postimage_reader,
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	git_index *postimage,
	git_diff *diff,
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	git_strmap *removed_paths,
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	size_t i,
	const git_apply_options *opts)
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{
	git_patch *patch = NULL;
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	git_buf pre_contents = GIT_BUF_INIT, post_contents = GIT_BUF_INIT;
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	const git_diff_delta *delta;
	char *filename = NULL;
	unsigned int mode;
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	git_oid pre_id, post_id;
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	git_filemode_t pre_filemode;
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	git_index_entry pre_entry, post_entry;
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	bool skip_preimage = false;
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	size_t pos;
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	int error;

	if ((error = git_patch_from_diff(&patch, diff, i)) < 0)
		goto done;

	delta = git_patch_get_delta(patch);

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	if (opts->delta_cb) {
		error = opts->delta_cb(delta, opts->payload);

		if (error) {
			if (error > 0)
				error = 0;

			goto done;
		}
	}

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	/*
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	 * Ensure that the file has not been deleted or renamed if we're
	 * applying a modification delta.
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	 */
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	if (delta->status != GIT_DELTA_RENAMED &&
	    delta->status != GIT_DELTA_ADDED) {
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		pos = git_strmap_lookup_index(removed_paths, delta->old_file.path);
		if (git_strmap_valid_index(removed_paths, pos)) {
			error = apply_err("path '%s' has been renamed or deleted", delta->old_file.path);
			goto done;
		}
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	}
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	/*
	 * We may be applying a second delta to an already seen file.  If so,
	 * use the already modified data in the postimage instead of the
	 * content from the index or working directory.  (Don't do this in
	 * the case of a rename, which must be specified before additional
	 * deltas since we apply deltas to the target filename.)
	 */
	if (delta->status != GIT_DELTA_RENAMED) {
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		if ((error = git_reader_read(&pre_contents, &pre_id, &pre_filemode,
		    postimage_reader, delta->old_file.path)) == 0) {
			skip_preimage = true;
		} else if (error == GIT_ENOTFOUND) {
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			git_error_clear();
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			error = 0;
		} else {
			goto done;
		}
	}

	if (!skip_preimage && delta->status != GIT_DELTA_ADDED) {
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		error = git_reader_read(&pre_contents, &pre_id, &pre_filemode,
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			preimage_reader, delta->old_file.path);
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		/* ENOTFOUND means the preimage was not found; apply failed. */
		if (error == GIT_ENOTFOUND)
			error = GIT_EAPPLYFAIL;
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		/* When applying to BOTH, the index did not match the workdir. */
		if (error == GIT_READER_MISMATCH)
			error = apply_err("%s: does not match index", delta->old_file.path);

		if (error < 0)
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			goto done;
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		/*
		 * We need to populate the preimage data structure with the
		 * contents that we are using as the preimage for this file.
		 * This allows us to apply patches to files that have been
		 * modified in the working directory.  During checkout,
		 * we will use this expected preimage as the baseline, and
		 * limit checkout to only the paths affected by patch
		 * application.  (Without this, we would fail to write the
		 * postimage contents to any file that had been modified
		 * from HEAD on-disk, even if the patch application succeeded.)
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		 * Use the contents from the delta where available - some
		 * fields may not be available, like the old file mode (eg in
		 * an exact rename situation) so trust the patch parsing to
		 * validate and use the preimage data in that case.
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		 */
		if (preimage) {
			memset(&pre_entry, 0, sizeof(git_index_entry));
			pre_entry.path = delta->old_file.path;
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			pre_entry.mode = delta->old_file.mode ? delta->old_file.mode : pre_filemode;
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			git_oid_cpy(&pre_entry.id, &pre_id);

			if ((error = git_index_add(preimage, &pre_entry)) < 0)
				goto done;
		}
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	}

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	if (delta->status != GIT_DELTA_DELETED) {
		if ((error = git_apply__patch(&post_contents, &filename, &mode,
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				pre_contents.ptr, pre_contents.size, patch, opts)) < 0 ||
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			(error = git_blob_create_frombuffer(&post_id, repo,
				post_contents.ptr, post_contents.size)) < 0)
			goto done;
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		memset(&post_entry, 0, sizeof(git_index_entry));
		post_entry.path = filename;
		post_entry.mode = mode;
		git_oid_cpy(&post_entry.id, &post_id);
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		if ((error = git_index_add(postimage, &post_entry)) < 0)
			goto done;
	}
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	if (delta->status == GIT_DELTA_RENAMED ||
	    delta->status == GIT_DELTA_DELETED)
		git_strmap_insert(removed_paths, delta->old_file.path, (char *)delta->old_file.path, &error);

	if (delta->status == GIT_DELTA_RENAMED ||
	    delta->status == GIT_DELTA_ADDED)
		git_strmap_delete(removed_paths, delta->new_file.path);

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done:
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	git_buf_dispose(&pre_contents);
	git_buf_dispose(&post_contents);
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	git__free(filename);
	git_patch_free(patch);

	return error;
}

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static int apply_deltas(
	git_repository *repo,
	git_reader *pre_reader,
	git_index *preimage,
	git_reader *post_reader,
	git_index *postimage,
	git_diff *diff,
	const git_apply_options *opts)
{
	git_strmap *removed_paths;
	size_t i;
lhchavez committed
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	int error = 0;
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	if (git_strmap_alloc(&removed_paths) < 0)
		return -1;

	for (i = 0; i < git_diff_num_deltas(diff); i++) {
		if ((error = apply_one(repo, pre_reader, preimage, post_reader, postimage, diff, removed_paths, i, opts)) < 0)
			goto done;
	}

done:
	git_strmap_free(removed_paths);
	return error;
}

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int git_apply_to_tree(
	git_index **out,
	git_repository *repo,
	git_tree *preimage,
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	git_diff *diff,
	const git_apply_options *given_opts)
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{
	git_index *postimage = NULL;
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	git_reader *pre_reader = NULL, *post_reader = NULL;
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	git_apply_options opts = GIT_APPLY_OPTIONS_INIT;
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	const git_diff_delta *delta;
	size_t i;
	int error = 0;

	assert(out && repo && preimage && diff);

	*out = NULL;

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	if (given_opts)
		memcpy(&opts, given_opts, sizeof(git_apply_options));

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	if ((error = git_reader_for_tree(&pre_reader, preimage)) < 0)
		goto done;

	/*
	 * put the current tree into the postimage as-is - the diff will
	 * replace any entries contained therein
	 */
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	if ((error = git_index_new(&postimage)) < 0 ||
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		(error = git_index_read_tree(postimage, preimage)) < 0 ||
		(error = git_reader_for_index(&post_reader, repo, postimage)) < 0)
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		goto done;

	/*
	 * Remove the old paths from the index before applying diffs -
	 * we need to do a full pass to remove them before adding deltas,
	 * in order to handle rename situations.
	 */
	for (i = 0; i < git_diff_num_deltas(diff); i++) {
		delta = git_diff_get_delta(diff, i);

		if ((error = git_index_remove(postimage,
				delta->old_file.path, 0)) < 0)
			goto done;
	}

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	if ((error = apply_deltas(repo, pre_reader, NULL, post_reader, postimage, diff, &opts)) < 0)
		goto done;
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	*out = postimage;

done:
	if (error < 0)
		git_index_free(postimage);

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	git_reader_free(pre_reader);
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	git_reader_free(post_reader);
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	return error;
}
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static int git_apply__to_workdir(
	git_repository *repo,
	git_diff *diff,
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	git_index *preimage,
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	git_index *postimage,
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	git_apply_location_t location,
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	git_apply_options *opts)
{
	git_vector paths = GIT_VECTOR_INIT;
	git_checkout_options checkout_opts = GIT_CHECKOUT_OPTIONS_INIT;
	const git_diff_delta *delta;
	size_t i;
	int error;

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	GIT_UNUSED(opts);

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	/*
	 * Limit checkout to the paths affected by the diff; this ensures
	 * that other modifications in the working directory are unaffected.
	 */
	if ((error = git_vector_init(&paths, git_diff_num_deltas(diff), NULL)) < 0)
		goto done;

	for (i = 0; i < git_diff_num_deltas(diff); i++) {
		delta = git_diff_get_delta(diff, i);

		if ((error = git_vector_insert(&paths, (void *)delta->old_file.path)) < 0)
			goto done;

		if (strcmp(delta->old_file.path, delta->new_file.path) &&
		    (error = git_vector_insert(&paths, (void *)delta->new_file.path)) < 0)
			goto done;
	}

	checkout_opts.checkout_strategy |= GIT_CHECKOUT_SAFE;
	checkout_opts.checkout_strategy |= GIT_CHECKOUT_DISABLE_PATHSPEC_MATCH;
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	checkout_opts.checkout_strategy |= GIT_CHECKOUT_DONT_WRITE_INDEX;
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	if (location == GIT_APPLY_LOCATION_WORKDIR)
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		checkout_opts.checkout_strategy |= GIT_CHECKOUT_DONT_UPDATE_INDEX;

	checkout_opts.paths.strings = (char **)paths.contents;
	checkout_opts.paths.count = paths.length;

698 699
	checkout_opts.baseline_index = preimage;

700 701 702 703 704 705 706 707 708 709
	error = git_checkout_index(repo, postimage, &checkout_opts);

done:
	git_vector_free(&paths);
	return error;
}

static int git_apply__to_index(
	git_repository *repo,
	git_diff *diff,
710
	git_index *preimage,
711 712 713 714 715 716 717 718 719
	git_index *postimage,
	git_apply_options *opts)
{
	git_index *index = NULL;
	const git_diff_delta *delta;
	const git_index_entry *entry;
	size_t i;
	int error;

720
	GIT_UNUSED(preimage);
721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763
	GIT_UNUSED(opts);

	if ((error = git_repository_index(&index, repo)) < 0)
		goto done;

	/* Remove deleted (or renamed) paths from the index. */
	for (i = 0; i < git_diff_num_deltas(diff); i++) {
		delta = git_diff_get_delta(diff, i);

		if (delta->status == GIT_DELTA_DELETED ||
		    delta->status == GIT_DELTA_RENAMED) {
			if ((error = git_index_remove(index, delta->old_file.path, 0)) < 0)
				goto done;
		}
	}

	/* Then add the changes back to the index. */
	for (i = 0; i < git_index_entrycount(postimage); i++) {
		entry = git_index_get_byindex(postimage, i);

		if ((error = git_index_add(index, entry)) < 0)
			goto done;
	}

done:
	git_index_free(index);
	return error;
}

/*
 * Handle the three application options ("locations"):
 *
 * GIT_APPLY_LOCATION_WORKDIR: the default, emulates `git apply`.
 * Applies the diff only to the workdir items and ignores the index
 * entirely.
 *
 * GIT_APPLY_LOCATION_INDEX: emulates `git apply --cached`.
 * Applies the diff only to the index items and ignores the workdir
 * completely.
 *
 * GIT_APPLY_LOCATION_BOTH: emulates `git apply --index`.
 * Applies the diff to both the index items and the working directory
 * items.
764 765 766 767 768
 */

int git_apply(
	git_repository *repo,
	git_diff *diff,
769 770
	git_apply_location_t location,
	const git_apply_options *given_opts)
771
{
772 773
	git_indexwriter indexwriter = GIT_INDEXWRITER_INIT;
	git_index *index = NULL, *preimage = NULL, *postimage = NULL;
774
	git_reader *pre_reader = NULL, *post_reader = NULL;
775
	git_apply_options opts = GIT_APPLY_OPTIONS_INIT;
776
	int error = GIT_EINVALID;
777 778 779

	assert(repo && diff);

780
	GIT_ERROR_CHECK_VERSION(
781 782 783 784 785 786 787 788 789 790
		given_opts, GIT_APPLY_OPTIONS_VERSION, "git_apply_options");

	if (given_opts)
		memcpy(&opts, given_opts, sizeof(git_apply_options));

	/*
	 * by default, we apply a patch directly to the working directory;
	 * in `--cached` or `--index` mode, we apply to the contents already
	 * in the index.
	 */
791
	switch (location) {
792 793 794 795
	case GIT_APPLY_LOCATION_BOTH:
		error = git_reader_for_workdir(&pre_reader, repo, true);
		break;
	case GIT_APPLY_LOCATION_INDEX:
796
		error = git_reader_for_index(&pre_reader, repo, NULL);
797 798 799 800 801 802 803
		break;
	case GIT_APPLY_LOCATION_WORKDIR:
		error = git_reader_for_workdir(&pre_reader, repo, false);
		break;
	default:
		assert(false);
	}
804 805 806 807 808

	if (error < 0)
		goto done;

	/*
809 810 811 812 813
	 * Build the preimage and postimage (differences).  Note that
	 * this is not the complete preimage or postimage, it only
	 * contains the files affected by the patch.  We want to avoid
	 * having the full repo index, so we will limit our checkout
	 * to only write these files that were affected by the diff.
814
	 */
815
	if ((error = git_index_new(&preimage)) < 0 ||
816 817
	    (error = git_index_new(&postimage)) < 0 ||
	    (error = git_reader_for_index(&post_reader, repo, postimage)) < 0)
818 819
		goto done;

820 821 822 823
	if ((error = git_repository_index(&index, repo)) < 0 ||
	    (error = git_indexwriter_init(&indexwriter, index)) < 0)
		goto done;

824 825
	if ((error = apply_deltas(repo, pre_reader, preimage, post_reader, postimage, diff, &opts)) < 0)
		goto done;
826

827
	switch (location) {
828
	case GIT_APPLY_LOCATION_BOTH:
829
		error = git_apply__to_workdir(repo, diff, preimage, postimage, location, &opts);
830 831
		break;
	case GIT_APPLY_LOCATION_INDEX:
832
		error = git_apply__to_index(repo, diff, preimage, postimage, &opts);
833 834
		break;
	case GIT_APPLY_LOCATION_WORKDIR:
835
		error = git_apply__to_workdir(repo, diff, preimage, postimage, location, &opts);
836 837 838
		break;
	default:
		assert(false);
839 840
	}

841 842 843
	if (error < 0)
		goto done;

844 845
	error = git_indexwriter_commit(&indexwriter);

846
done:
847
	git_indexwriter_cleanup(&indexwriter);
848
	git_index_free(postimage);
849
	git_index_free(preimage);
850
	git_index_free(index);
851
	git_reader_free(pre_reader);
852
	git_reader_free(post_reader);
853 854 855

	return error;
}