thodg/got/lib/patch.c

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• Hash : eb81bc23
  Author :
  Date : 2022-06-28T13:27:12
  

  move got_opentempfd out of open_blob. ok stsp@

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• lib/patch.c

• /*
   * Copyright (c) 2022 Omar Polo <op@openbsd.org>
   *
   * Permission to use, copy, modify, and distribute this software for any
   * purpose with or without fee is hereby granted, provided that the above
   * copyright notice and this permission notice appear in all copies.
   *
   * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
   * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
   * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
   * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
   * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
   * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
   *
   * Apply patches.
   *
   * Things that we may want to support:
   *     + support indented patches?
   *     + support other kinds of patches?
   */
  
  #include <sys/types.h>
  #include <sys/queue.h>
  #include <sys/socket.h>
  #include <sys/stat.h>
  #include <sys/uio.h>
  
  #include <errno.h>
  #include <limits.h>
  #include <sha1.h>
  #include <stdint.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <unistd.h>
  #include <imsg.h>
  
  #include "got_error.h"
  #include "got_object.h"
  #include "got_path.h"
  #include "got_reference.h"
  #include "got_cancel.h"
  #include "got_worktree.h"
  #include "got_repository.h"
  #include "got_opentemp.h"
  #include "got_patch.h"
  
  #include "got_lib_delta.h"
  #include "got_lib_diff.h"
  #include "got_lib_object.h"
  #include "got_lib_privsep.h"
  #include "got_lib_sha1.h"
  
  #define MIN(a, b) ((a) < (b) ? (a) : (b))
  
  struct got_patch_hunk {
  	STAILQ_ENTRY(got_patch_hunk) entries;
  	const struct got_error *err;
  	int	offset;
  	int	old_nonl;
  	int	new_nonl;
  	int	old_from;
  	int	old_lines;
  	int	new_from;
  	int	new_lines;
  	size_t	len;
  	size_t	cap;
  	char	**lines;
  };
  
  STAILQ_HEAD(got_patch_hunk_head, got_patch_hunk);
  struct got_patch {
  	char	*old;
  	char	*new;
  	char	 cid[41];
  	char	 blob[41];
  	struct got_patch_hunk_head head;
  };
  
  struct patch_args {
  	got_patch_progress_cb progress_cb;
  	void	*progress_arg;
  	struct got_patch_hunk_head *head;
  };
  
  static const struct got_error *
  send_patch(struct imsgbuf *ibuf, int fd)
  {
  	const struct got_error *err = NULL;
  
  	if (imsg_compose(ibuf, GOT_IMSG_PATCH_FILE, 0, 0, fd,
  	    NULL, 0) == -1) {
  		err = got_error_from_errno(
  		    "imsg_compose GOT_IMSG_PATCH_FILE");
  		close(fd);
  		return err;
  	}
  
  	if (imsg_flush(ibuf) == -1) {
  		err = got_error_from_errno("imsg_flush");
  		imsg_clear(ibuf);
  	}
  
  	return err;
  }
  
  static void
  patch_free(struct got_patch *p)
  {
  	struct got_patch_hunk *h;
  	size_t i;
  
  	while (!STAILQ_EMPTY(&p->head)) {
  		h = STAILQ_FIRST(&p->head);
  		STAILQ_REMOVE_HEAD(&p->head, entries);
  
  		for (i = 0; i < h->len; ++i)
  			free(h->lines[i]);
  		free(h->lines);
  		free(h);
  	}
  
  	free(p->new);
  	free(p->old);
  
  	memset(p, 0, sizeof(*p));
  	STAILQ_INIT(&p->head);
  }
  
  static const struct got_error *
  pushline(struct got_patch_hunk *h, const char *line)
  {
  	void 	*t;
  	size_t	 newcap;
  
  	if (h->len == h->cap) {
  		if ((newcap = h->cap * 1.5) == 0)
  			newcap = 16;
  		t = recallocarray(h->lines, h->cap, newcap,
  		    sizeof(h->lines[0]));
  		if (t == NULL)
  			return got_error_from_errno("recallocarray");
  		h->lines = t;
  		h->cap = newcap;
  	}
  
  	if ((t = strdup(line)) == NULL)
  		return got_error_from_errno("strdup");
  
  	h->lines[h->len++] = t;
  	return NULL;
  }
  
  static const struct got_error *
  recv_patch(struct imsgbuf *ibuf, int *done, struct got_patch *p, int strip)
  {
  	const struct got_error *err = NULL;
  	struct imsg imsg;
  	struct got_imsg_patch_hunk hdr;
  	struct got_imsg_patch patch;
  	struct got_patch_hunk *h = NULL;
  	size_t datalen;
  	int lastmode = -1;
  
  	memset(p, 0, sizeof(*p));
  	STAILQ_INIT(&p->head);
  
  	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
  	if (err)
  		return err;
  	if (imsg.hdr.type == GOT_IMSG_PATCH_EOF) {
  		*done = 1;
  		goto done;
  	}
  	if (imsg.hdr.type != GOT_IMSG_PATCH) {
  		err = got_error(GOT_ERR_PRIVSEP_MSG);
  		goto done;
  	}
  	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
  	if (datalen != sizeof(patch)) {
  		err = got_error(GOT_ERR_PRIVSEP_LEN);
  		goto done;
  	}
  	memcpy(&patch, imsg.data, sizeof(patch));
  
  	if (patch.old[sizeof(patch.old)-1] != '\0' ||
  	    patch.new[sizeof(patch.new)-1] != '\0' ||
  	    patch.cid[sizeof(patch.cid)-1] != '\0' ||
  	    patch.blob[sizeof(patch.blob)-1] != '\0') {
  		err = got_error(GOT_ERR_PRIVSEP_LEN);
  		goto done;
  	}
  
  	if (*patch.cid != '\0')
  		strlcpy(p->cid, patch.cid, sizeof(p->cid));
  
  	if (*patch.blob != '\0')
  		strlcpy(p->blob, patch.blob, sizeof(p->blob));
  
  	/* automatically set strip=1 for git-style diffs */
  	if (strip == -1 && patch.git &&
  	    (*patch.old == '\0' || !strncmp(patch.old, "a/", 2)) &&
  	    (*patch.new == '\0' || !strncmp(patch.new, "b/", 2)))
  		strip = 1;
  
  	/* prefer the new name if not /dev/null for not git-style diffs */
  	if (!patch.git && *patch.new != '\0' && *patch.old != '\0') {
  		err = got_path_strip(&p->old, patch.new, strip);
  		if (err)
  			goto done;
  	} else if (*patch.old != '\0') {
  		err = got_path_strip(&p->old, patch.old, strip);
  		if (err)
  			goto done;
  	}
  
  	if (*patch.new != '\0') {
  		err = got_path_strip(&p->new, patch.new, strip);
  		if (err)
  			goto done;
  	}
  
  	if (p->old == NULL && p->new == NULL) {
  		err = got_error(GOT_ERR_PATCH_MALFORMED);
  		goto done;
  	}
  
  	imsg_free(&imsg);
  
  	for (;;) {
  		char *t;
  
  		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
  		if (err) {
  			patch_free(p);
  			return err;
  		}
  
  		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
  		switch (imsg.hdr.type) {
  		case GOT_IMSG_PATCH_DONE:
  			if (h != NULL && h->len == 0)
  				err = got_error(GOT_ERR_PATCH_MALFORMED);
  			goto done;
  		case GOT_IMSG_PATCH_HUNK:
  			if (h != NULL &&
  			    (h->len == 0 || h->old_nonl || h->new_nonl)) {
  				err = got_error(GOT_ERR_PATCH_MALFORMED);
  				goto done;
  			}
  			lastmode = -1;
  			if (datalen != sizeof(hdr)) {
  				err = got_error(GOT_ERR_PRIVSEP_LEN);
  				goto done;
  			}
  			memcpy(&hdr, imsg.data, sizeof(hdr));
  			if (hdr.oldfrom < 0 || hdr.newfrom < 0) {
  				err = got_error(GOT_ERR_PRIVSEP_LEN);
  				goto done;
  			}
  			if ((h = calloc(1, sizeof(*h))) == NULL) {
  				err = got_error_from_errno("calloc");
  				goto done;
  			}
  			h->old_from = hdr.oldfrom;
  			h->old_lines = hdr.oldlines;
  			h->new_from = hdr.newfrom;
  			h->new_lines = hdr.newlines;
  			STAILQ_INSERT_TAIL(&p->head, h, entries);
  			break;
  		case GOT_IMSG_PATCH_LINE:
  			if (h == NULL) {
  				err = got_error(GOT_ERR_PRIVSEP_MSG);
  				goto done;
  			}
  			t = imsg.data;
  			/* at least one char */
  			if (datalen < 2 || t[datalen-1] != '\0') {
  				err = got_error(GOT_ERR_PRIVSEP_MSG);
  				goto done;
  			}
  			if (*t != ' ' && *t != '-' && *t != '+' &&
  			    *t != '\\') {
  				err = got_error(GOT_ERR_PRIVSEP_MSG);
  				goto done;
  			}
  
  			if (*t != '\\')
  				err = pushline(h, t);
  			else if (lastmode == '-')
  				h->old_nonl = 1;
  			else if (lastmode == '+')
  				h->new_nonl = 1;
  			else
  				err = got_error(GOT_ERR_PATCH_MALFORMED);
  
  			if (err)
  				goto done;
  
  			lastmode = *t;
  			break;
  		default:
  			err = got_error(GOT_ERR_PRIVSEP_MSG);
  			goto done;
  		}
  
  		imsg_free(&imsg);
  	}
  
  done:
  	if (err)
  		patch_free(p);
  
  	imsg_free(&imsg);
  	return err;
  }
  
  /*
   * Copy data from orig starting at copypos until pos into tmp.
   * If pos is -1, copy until EOF.
   */
  static const struct got_error *
  copy(FILE *tmp, FILE *orig, off_t copypos, off_t pos)
  {
  	char buf[BUFSIZ];
  	size_t len, r, w;
  
  	if (fseeko(orig, copypos, SEEK_SET) == -1)
  		return got_error_from_errno("fseeko");
  
  	while (pos == -1 || copypos < pos) {
  		len = sizeof(buf);
  		if (pos > 0)
  			len = MIN(len, (size_t)pos - copypos);
  		r = fread(buf, 1, len, orig);
  		if (r != len && ferror(orig))
  			return got_error_from_errno("fread");
  		w = fwrite(buf, 1, r, tmp);
  		if (w != r)
  			return got_error_from_errno("fwrite");
  		copypos += len;
  		if (r != len && feof(orig)) {
  			if (pos == -1)
  				return NULL;
  			return got_error(GOT_ERR_HUNK_FAILED);
  		}
  	}
  	return NULL;
  }
  
  static const struct got_error *
  locate_hunk(FILE *orig, struct got_patch_hunk *h, off_t *pos, int *lineno)
  {
  	const struct got_error *err = NULL;
  	char *line = NULL;
  	char mode = *h->lines[0];
  	size_t linesize = 0;
  	ssize_t linelen;
  	off_t match = -1;
  	int match_lineno = -1;
  
  	for (;;) {
  		linelen = getline(&line, &linesize, orig);
  		if (linelen == -1) {
  			if (ferror(orig))
  				err = got_error_from_errno("getline");
  			else if (match == -1)
  				err = got_error(GOT_ERR_HUNK_FAILED);
  			break;
  		}
  		if (line[linelen - 1] == '\n')
  			line[linelen - 1] = '\0';
  		(*lineno)++;
  
  		if ((mode == ' ' && !strcmp(h->lines[0] + 1, line)) ||
  		    (mode == '-' && !strcmp(h->lines[0] + 1, line)) ||
  		    (mode == '+' && *lineno == h->old_from)) {
  			match = ftello(orig);
  			if (match == -1) {
  				err = got_error_from_errno("ftello");
  				break;
  			}
  			match -= linelen;
  			match_lineno = (*lineno)-1;
  		}
  
  		if (*lineno >= h->old_from && match != -1)
  			break;
  	}
  
  	if (err == NULL) {
  		*pos = match;
  		*lineno = match_lineno;
  		if (fseeko(orig, match, SEEK_SET) == -1)
  			err = got_error_from_errno("fseeko");
  	}
  
  	free(line);
  	return err;
  }
  
  static const struct got_error *
  test_hunk(FILE *orig, struct got_patch_hunk *h)
  {
  	const struct got_error *err = NULL;
  	char *line = NULL;
  	size_t linesize = 0, i = 0;
  	ssize_t linelen;
  
  	for (i = 0; i < h->len; ++i) {
  		switch (*h->lines[i]) {
  		case '+':
  			continue;
  		case ' ':
  		case '-':
  			linelen = getline(&line, &linesize, orig);
  			if (linelen == -1) {
  				if (ferror(orig))
  					err = got_error_from_errno("getline");
  				else
  					err = got_error(
  					    GOT_ERR_HUNK_FAILED);
  				goto done;
  			}
  			if (line[linelen - 1] == '\n')
  				line[linelen - 1] = '\0';
  			if (strcmp(h->lines[i] + 1, line)) {
  				err = got_error(GOT_ERR_HUNK_FAILED);
  				goto done;
  			}
  			break;
  		}
  	}
  
  done:
  	free(line);
  	return err;
  }
  
  static const struct got_error *
  apply_hunk(FILE *tmp, struct got_patch_hunk *h, int *lineno)
  {
  	size_t i, new = 0;
  
  	for (i = 0; i < h->len; ++i) {
  		switch (*h->lines[i]) {
  		case ' ':
  			if (fprintf(tmp, "%s\n", h->lines[i] + 1) < 0)
  				return got_error_from_errno("fprintf");
  			/* fallthrough */
  		case '-':
  			(*lineno)++;
  			break;
  		case '+':
  			new++;
  			if (fprintf(tmp, "%s", h->lines[i] + 1) < 0)
  				return got_error_from_errno("fprintf");
  			if (new != h->new_lines || !h->new_nonl) {
  				if (fprintf(tmp, "\n") < 0)
  					return got_error_from_errno(
  					    "fprintf");
  			}
  			break;
  		}
  	}
  	return NULL;
  }
  
  static const struct got_error *
  patch_file(struct got_patch *p, FILE *orig, FILE *tmp, mode_t *mode)
  {
  	const struct got_error *err = NULL;
  	struct got_patch_hunk *h;
  	struct stat sb;
  	int lineno = 0;
  	off_t copypos, pos;
  	char *line = NULL;
  	size_t linesize = 0;
  	ssize_t linelen;
  
  	if (p->old == NULL) {				/* create */
  		h = STAILQ_FIRST(&p->head);
  		if (h == NULL || STAILQ_NEXT(h, entries) != NULL)
  			return got_error(GOT_ERR_PATCH_MALFORMED);
  		return apply_hunk(tmp, h, &lineno);
  	}
  
  	if (fstat(fileno(orig), &sb) == -1)
  		return got_error_from_errno("fstat");
  	*mode = sb.st_mode;
  
  	copypos = 0;
  	STAILQ_FOREACH(h, &p->head, entries) {
  	tryagain:
  		err = locate_hunk(orig, h, &pos, &lineno);
  		if (err != NULL && err->code == GOT_ERR_HUNK_FAILED)
  			h->err = err;
  		if (err != NULL)
  			return err;
  		err = copy(tmp, orig, copypos, pos);
  		if (err != NULL)
  			return err;
  		copypos = pos;
  
  		err = test_hunk(orig, h);
  		if (err != NULL && err->code == GOT_ERR_HUNK_FAILED) {
  			/*
  			 * try to apply the hunk again starting the search
  			 * after the previous partial match.
  			 */
  			if (fseeko(orig, pos, SEEK_SET) == -1)
  				return got_error_from_errno("fseeko");
  			linelen = getline(&line, &linesize, orig);
  			if (linelen == -1)
  				return got_error_from_errno("getline");
  			lineno++;
  			goto tryagain;
  		}
  		if (err != NULL)
  			return err;
  
  		if (lineno + 1 != h->old_from)
  			h->offset = lineno + 1 - h->old_from;
  
  		err = apply_hunk(tmp, h, &lineno);
  		if (err != NULL)
  			return err;
  
  		copypos = ftello(orig);
  		if (copypos == -1)
  			return got_error_from_errno("ftello");
  	}
  
  	if (p->new == NULL && sb.st_size != copypos) {
  		h = STAILQ_FIRST(&p->head);
  		h->err = got_error(GOT_ERR_HUNK_FAILED);
  		err = h->err;
  	} else if (!feof(orig))
  		err = copy(tmp, orig, copypos, -1);
  
  	return err;
  }
  
  static const struct got_error *
  report_progress(struct patch_args *pa, const char *old, const char *new,
      unsigned char status, const struct got_error *orig_error)
  {
  	const struct got_error *err;
  	struct got_patch_hunk *h;
  
  	err = pa->progress_cb(pa->progress_arg, old, new, status,
  	    orig_error, 0, 0, 0, 0, 0, NULL);
  	if (err)
  		return err;
  
  	STAILQ_FOREACH(h, pa->head, entries) {
  		if (h->offset == 0 && h->err == NULL)
  			continue;
  
  		err = pa->progress_cb(pa->progress_arg, old, new, 0, NULL,
  		    h->old_from, h->old_lines, h->new_from, h->new_lines,
  		    h->offset, h->err);
  		if (err)
  			return err;
  	}
  
  	return NULL;
  }
  
  static const struct got_error *
  patch_delete(void *arg, unsigned char status, unsigned char staged_status,
      const char *path)
  {
  	return report_progress(arg, path, NULL, status, NULL);
  }
  
  static const struct got_error *
  patch_add(void *arg, unsigned char status, const char *path)
  {
  	return report_progress(arg, NULL, path, status, NULL);
  }
  
  static const struct got_error *
  open_blob(char **path, FILE **fp, const char *blobid,
      struct got_repository *repo)
  {
  	const struct got_error *err = NULL;
  	struct got_blob_object *blob = NULL;
  	struct got_object_id id, *idptr, *matched_id = NULL;
  	int fd = -1;
  
  	*fp = NULL;
  	*path = NULL;
  
  	if (strlen(blobid) != SHA1_DIGEST_STRING_LENGTH - 1) {
  		err = got_repo_match_object_id(&matched_id, NULL, blobid,
  		    GOT_OBJ_TYPE_BLOB, NULL /* do not resolve tags */,
  		    repo);
  		if (err)
  			return err;
  		idptr = matched_id;
  	} else {
  		if (!got_parse_sha1_digest(id.sha1, blobid))
  			return got_error(GOT_ERR_BAD_OBJ_ID_STR);
  		idptr = &id;
  	}
  
  	fd = got_opentempfd();
  	if (fd == -1) {
  		err = got_error_from_errno("got_opentempfd");
  		goto done;
  	}
  
  	err = got_object_open_as_blob(&blob, repo, idptr, 8192, fd);
  	if (err)
  		goto done;
  
  	err = got_opentemp_named(path, fp, GOT_TMPDIR_STR "/got-patch-blob");
  	if (err)
  		goto done;
  
  	err = got_object_blob_dump_to_file(NULL, NULL, NULL, *fp, blob);
  	if (err)
  		goto done;
  
  done:
  	if (fd != -1 && close(fd) == -1 && err == NULL)
  		err = got_error_from_errno("close");
  	if (blob)
  		got_object_blob_close(blob);
  	if (matched_id != NULL)
  		free(matched_id);
  	if (err) {
  		if (*fp != NULL)
  			fclose(*fp);
  		if (*path != NULL)
  			unlink(*path);
  		free(*path);
  		*fp = NULL;
  		*path = NULL;
  	}
  	return err;
  }
  
  static const struct got_error *
  apply_patch(int *overlapcnt, struct got_worktree *worktree,
      struct got_repository *repo, struct got_fileindex *fileindex,
      const char *old, const char *new, struct got_patch *p, int nop,
      struct patch_args *pa, got_cancel_cb cancel_cb, void *cancel_arg)
  {
  	const struct got_error *err = NULL;
  	int do_merge = 0, file_renamed = 0;
  	char *oldlabel = NULL, *newlabel = NULL, *anclabel = NULL;
  	char *oldpath = NULL, *newpath = NULL;
  	char *tmppath = NULL, *template = NULL, *parent = NULL;
  	char *apath = NULL, *mergepath = NULL;
  	FILE *oldfile = NULL, *tmpfile = NULL, *afile = NULL, *mergefile = NULL;
  	int outfd;
  	const char *outpath;
  	mode_t mode = GOT_DEFAULT_FILE_MODE;
  
  	*overlapcnt = 0;
  
  	/* don't run the diff3 merge on creations/deletions */
  	if (*p->blob != '\0' && p->old != NULL && p->new != NULL) {
  		err = open_blob(&apath, &afile, p->blob, repo);
  		/*
  		 * ignore failures to open this blob, we might have
  		 * parsed gibberish.
  		 */
  		if (err && !(err->code == GOT_ERR_ERRNO && errno == ENOENT) &&
  		    err->code != GOT_ERR_NO_OBJ)
  			return err;
  		else if (err == NULL)
  			do_merge = 1;
  		err = NULL;
  	}
  
  	if (asprintf(&oldpath, "%s/%s", got_worktree_get_root_path(worktree),
  	    old) == -1) {
  		err = got_error_from_errno("asprintf");
  		goto done;
  	}
  
  	if (asprintf(&newpath, "%s/%s", got_worktree_get_root_path(worktree),
  	    new) == -1) {
  		err = got_error_from_errno("asprintf");
  		goto done;
  	}
  
  	file_renamed = strcmp(oldpath, newpath);
  
  	if (asprintf(&template, "%s/got-patch",
  	    got_worktree_get_root_path(worktree)) == -1) {
  		err = got_error_from_errno(template);
  		goto done;
  	}
  
  	if (p->old != NULL && (oldfile = fopen(oldpath, "r")) == NULL) {
  		err = got_error_from_errno2("open", oldpath);
  		goto done;
  	}
  
  	err = got_opentemp_named(&tmppath, &tmpfile, template);
  	if (err)
  		goto done;
  	outpath = tmppath;
  	outfd = fileno(tmpfile);
  	err = patch_file(p, afile != NULL ? afile : oldfile, tmpfile, &mode);
  	if (err)
  		goto done;
  
  	if (do_merge) {
  		const char *type, *id;
  
  		if (fseeko(afile, 0, SEEK_SET) == -1 ||
  		    fseeko(oldfile, 0, SEEK_SET) == -1 ||
  		    fseeko(tmpfile, 0, SEEK_SET) == -1) {
  			err = got_error_from_errno("fseeko");
  			goto done;
  		}
  
  		if (asprintf(&oldlabel, "--- %s", p->old) == -1) {
  			err = got_error_from_errno("asprintf");
  			oldlabel = NULL;
  			goto done;
  		}
  
  		if (asprintf(&newlabel, "+++ %s", p->new) == -1) {
  			err = got_error_from_errno("asprintf");
  			newlabel = NULL;
  			goto done;
  		}
  
  		if (*p->cid != '\0') {
  			type = "commit";
  			id = p->cid;
  		} else {
  			type = "blob";
  			id = p->blob;
  		}
  
  		if (asprintf(&anclabel, "%s %s", type, id) == -1) {
  			err = got_error_from_errno("asprintf");
  			anclabel = NULL;
  			goto done;
  		}
  
  		err = got_opentemp_named(&mergepath, &mergefile, template);
  		if (err)
  			goto done;
  		outpath = mergepath;
  		outfd = fileno(mergefile);
  
  		err = got_merge_diff3(overlapcnt, outfd, tmpfile, afile,
  		    oldfile, oldlabel, anclabel, newlabel,
  		    GOT_DIFF_ALGORITHM_PATIENCE);
  		if (err)
  			goto done;
  	}
  
  	if (nop)
  		goto done;
  
  	if (p->old != NULL && p->new == NULL) {
  		err = got_worktree_patch_schedule_rm(old, repo, worktree,
  		    fileindex, patch_delete, pa);
  		goto done;
  	}
  
  	if (fchmod(outfd, mode) == -1) {
  		err = got_error_from_errno2("chmod", tmppath);
  		goto done;
  	}
  
  	if (rename(outpath, newpath) == -1) {
  		if (errno != ENOENT) {
  			err = got_error_from_errno3("rename", outpath,
  			    newpath);
  			goto done;
  		}
  
  		err = got_path_dirname(&parent, newpath);
  		if (err != NULL)
  			goto done;
  		err = got_path_mkdir(parent);
  		if (err != NULL)
  			goto done;
  		if (rename(outpath, newpath) == -1) {
  			err = got_error_from_errno3("rename", outpath,
  			    newpath);
  			goto done;
  		}
  	}
  
  	if (file_renamed) {
  		err = got_worktree_patch_schedule_rm(old, repo, worktree,
  		    fileindex, patch_delete, pa);
  		if (err == NULL)
  			err = got_worktree_patch_schedule_add(new, repo,
  			    worktree, fileindex, patch_add,
  			    pa);
  		if (err)
  			unlink(newpath);
  	} else if (p->old == NULL) {
  		err = got_worktree_patch_schedule_add(new, repo, worktree,
  		    fileindex, patch_add, pa);
  		if (err)
  			unlink(newpath);
  	} else if (*overlapcnt != 0)
  		err = report_progress(pa, old, new, GOT_STATUS_CONFLICT, NULL);
  	else if (do_merge)
  		err = report_progress(pa, old, new, GOT_STATUS_MERGE, NULL);
  	else
  		err = report_progress(pa, old, new, GOT_STATUS_MODIFY, NULL);
  
  done:
  	free(parent);
  	free(template);
  
  	if (tmppath != NULL)
  		unlink(tmppath);
  	if (tmpfile != NULL && fclose(tmpfile) == EOF && err == NULL)
  		err = got_error_from_errno("fclose");
  	free(tmppath);
  
  	free(oldpath);
  	if (oldfile != NULL && fclose(oldfile) == EOF && err == NULL)
  		err = got_error_from_errno("fclose");
  
  	if (apath != NULL)
  		unlink(apath);
  	if (afile != NULL && fclose(afile) == EOF && err == NULL)
  		err = got_error_from_errno("fclose");
  	free(apath);
  
  	if (mergepath != NULL)
  		unlink(mergepath);
  	if (mergefile != NULL && fclose(mergefile) == EOF && err == NULL)
  		err = got_error_from_errno("fclose");
  	free(mergepath);
  
  	free(newpath);
  	free(oldlabel);
  	free(newlabel);
  	free(anclabel);
  	return err;
  }
  
  static void
  reverse_patch(struct got_patch *p)
  {
  	struct got_patch_hunk *h;
  	size_t i;
  	int tmp;
  
  	STAILQ_FOREACH(h, &p->head, entries) {
  		tmp = h->old_from;
  		h->old_from = h->new_from;
  		h->new_from = tmp;
  
  		tmp = h->old_lines;
  		h->old_lines = h->new_lines;
  		h->new_lines = tmp;
  
  		tmp = h->old_nonl;
  		h->old_nonl = h->new_nonl;
  		h->new_nonl = tmp;
  
  		for (i = 0; i < h->len; ++i) {
  			if (*h->lines[i] == '+')
  				*h->lines[i] = '-';
  			else if (*h->lines[i] == '-')
  				*h->lines[i] = '+';
  		}
  	}
  }
  
  const struct got_error *
  got_patch(int fd, struct got_worktree *worktree, struct got_repository *repo,
      int nop, int strip, int reverse, got_patch_progress_cb progress_cb,
      void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
  {
  	const struct got_error *err = NULL, *complete_err = NULL;
  	struct got_fileindex *fileindex = NULL;
  	char *fileindex_path = NULL;
  	char *oldpath, *newpath;
  	struct imsgbuf *ibuf;
  	int imsg_fds[2] = {-1, -1};
  	int overlapcnt, done = 0, failed = 0;
  	pid_t pid;
  
  	ibuf = calloc(1, sizeof(*ibuf));
  	if (ibuf == NULL) {
  		err = got_error_from_errno("calloc");
  		goto done;
  	}
  
  	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
  		err = got_error_from_errno("socketpair");
  		goto done;
  	}
  
  	pid = fork();
  	if (pid == -1) {
  		err = got_error_from_errno("fork");
  		goto done;
  	} else if (pid == 0) {
  		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_PATCH,
  		    NULL);
  		/* not reached */
  	}
  
  	if (close(imsg_fds[1]) == -1) {
  		err = got_error_from_errno("close");
  		goto done;
  	}
  	imsg_fds[1] = -1;
  	imsg_init(ibuf, imsg_fds[0]);
  
  	err = send_patch(ibuf, fd);
  	fd = -1;
  	if (err)
  		goto done;
  
  	err = got_worktree_patch_prepare(&fileindex, &fileindex_path,
  	    worktree);
  	if (err)
  		goto done;
  
  	while (!done && err == NULL) {
  		struct got_patch p;
  		struct patch_args pa;
  
  		pa.progress_cb = progress_cb;
  		pa.progress_arg = progress_arg;
  		pa.head = &p.head;
  
  		err = recv_patch(ibuf, &done, &p, strip);
  		if (err || done)
  			break;
  
  		if (reverse)
  			reverse_patch(&p);
  
  		err = got_worktree_patch_check_path(p.old, p.new, &oldpath,
  		    &newpath, worktree, repo, fileindex);
  		if (err == NULL)
  			err = apply_patch(&overlapcnt, worktree, repo,
  			    fileindex, oldpath, newpath, &p, nop, &pa,
  			    cancel_cb, cancel_arg);
  		if (err != NULL) {
  			failed = 1;
  			/* recoverable errors */
  			if (err->code == GOT_ERR_FILE_STATUS ||
  			    (err->code == GOT_ERR_ERRNO && errno == ENOENT))
  				err = report_progress(&pa, p.old, p.new,
  				    GOT_STATUS_CANNOT_UPDATE, err);
  			else if (err->code == GOT_ERR_HUNK_FAILED)
  				err = report_progress(&pa, p.old, p.new,
  				    GOT_STATUS_CANNOT_UPDATE, NULL);
  		}
  		if (overlapcnt != 0)
  			failed = 1;
  
  		free(oldpath);
  		free(newpath);
  		patch_free(&p);
  
  		if (err)
  			break;
  	}
  
  done:
  	if (fileindex != NULL)
  		complete_err = got_worktree_patch_complete(fileindex,
  		    fileindex_path);
  	if (complete_err && err == NULL)
  		err = complete_err;
  	free(fileindex_path);
  	if (fd != -1 && close(fd) == -1 && err == NULL)
  		err = got_error_from_errno("close");
  	if (ibuf != NULL)
  		imsg_clear(ibuf);
  	if (imsg_fds[0] != -1 && close(imsg_fds[0]) == -1 && err == NULL)
  		err = got_error_from_errno("close");
  	if (imsg_fds[1] != -1 && close(imsg_fds[1]) == -1 && err == NULL)
  		err = got_error_from_errno("close");
  	if (err == NULL && failed)
  		err = got_error(GOT_ERR_PATCH_FAILED);
  	return err;
  }
  

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