/*
* 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_opentemp.h"
#include "got_patch.h"
#include "got_lib_delta.h"
#include "got_lib_object.h"
#include "got_lib_privsep.h"
#define MIN(a, b) ((a) < (b) ? (a) : (b))
struct got_patch_hunk {
STAILQ_ENTRY(got_patch_hunk) entries;
const struct got_error *err;
long offset;
int nonl;
long old_from;
long old_lines;
long new_from;
long 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;
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);
}
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)
{
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;
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 != '\0' && (p->old = strdup(patch.old)) == NULL) {
err = got_error_from_errno("strdup");
goto done;
}
if (*patch.new != '\0' && (p->new = strdup(patch.new)) == NULL) {
err = got_error_from_errno("strdup");
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)
return err;
switch (imsg.hdr.type) {
case GOT_IMSG_PATCH_DONE:
goto done;
case GOT_IMSG_PATCH_HUNK:
if (h != NULL && h->nonl) {
err = got_error(GOT_ERR_PATCH_MALFORMED);
goto done;
}
datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
if (datalen != sizeof(hdr)) {
err = got_error(GOT_ERR_PRIVSEP_LEN);
goto done;
}
memcpy(&hdr, imsg.data, sizeof(hdr));
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;
}
datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
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 (h->nonl)
err = got_error(GOT_ERR_PATCH_MALFORMED);
if (*t == '\\')
h->nonl = 1;
else
err = pushline(h, t);
if (err)
goto done;
break;
default:
err = got_error(GOT_ERR_PRIVSEP_MSG);
goto done;
}
imsg_free(&imsg);
}
done:
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 (fseek(orig, copypos, SEEK_SET) == -1)
return got_error_from_errno("fseek");
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, long *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;
long 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 (fseek(orig, match, SEEK_SET) == -1)
err = got_error_from_errno("fseek");
}
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, long *lineno)
{
size_t i = 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 '+':
if (fprintf(tmp, "%s", h->lines[i] + 1) < 0)
return got_error_from_errno("fprintf");
if (i != h->len - 1 || !h->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, const char *path, FILE *tmp, int nop,
mode_t *mode)
{
const struct got_error *err = NULL;
struct got_patch_hunk *h;
struct stat sb;
long lineno = 0;
FILE *orig;
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);
if (nop)
return NULL;
return apply_hunk(tmp, h, &lineno);
}
if ((orig = fopen(path, "r")) == NULL) {
err = got_error_from_errno2("fopen", path);
goto done;
}
if (fstat(fileno(orig), &sb) == -1) {
err = got_error_from_errno("fstat");
goto done;
}
*mode = sb.st_mode;
copypos = 0;
STAILQ_FOREACH(h, &p->head, entries) {
if (h->lines == NULL)
break;
tryagain:
err = locate_hunk(orig, h, &pos, &lineno);
if (err != NULL && err->code == GOT_ERR_HUNK_FAILED)
h->err = err;
if (err != NULL)
goto done;
if (!nop)
err = copy(tmp, orig, copypos, pos);
if (err != NULL)
goto done;
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 (fseek(orig, pos, SEEK_SET) == -1) {
err = got_error_from_errno("fseek");
goto done;
}
linelen = getline(&line, &linesize, orig);
if (linelen == -1) {
err = got_error_from_errno("getline");
goto done;
}
lineno++;
goto tryagain;
}
if (err != NULL)
goto done;
if (lineno + 1 != h->old_from)
h->offset = lineno + 1 - h->old_from;
if (!nop)
err = apply_hunk(tmp, h, &lineno);
if (err != NULL)
goto done;
copypos = ftello(orig);
if (copypos == -1) {
err = got_error_from_errno("ftello");
goto done;
}
}
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 (!nop && !feof(orig))
err = copy(tmp, orig, copypos, -1);
done:
if (orig != NULL)
fclose(orig);
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 *
apply_patch(struct got_worktree *worktree, struct got_repository *repo,
const char *oldpath, const char *newpath, struct got_patch *p,
int nop, struct patch_args *pa, got_cancel_cb cancel_cb, void *cancel_arg)
{
const struct got_error *err = NULL;
struct got_pathlist_head oldpaths, newpaths;
struct got_pathlist_entry *pe;
int file_renamed = 0;
char *tmppath = NULL, *template = NULL, *parent = NULL;;
FILE *tmp = NULL;
mode_t mode = GOT_DEFAULT_FILE_MODE;
TAILQ_INIT(&oldpaths);
TAILQ_INIT(&newpaths);
err = got_pathlist_insert(&pe, &oldpaths, oldpath, NULL);
if (err)
goto done;
err = got_pathlist_insert(&pe, &newpaths, newpath, NULL);
if (err)
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 (!nop)
err = got_opentemp_named(&tmppath, &tmp, template);
if (err)
goto done;
err = patch_file(p, oldpath, tmp, nop, &mode);
if (err)
goto done;
if (nop)
goto done;
if (p->old != NULL && p->new == NULL) {
err = got_worktree_schedule_delete(worktree, &oldpaths,
0, NULL, patch_delete, pa, repo, 0, 0);
goto done;
}
if (fchmod(fileno(tmp), mode) == -1) {
err = got_error_from_errno2("chmod", newpath);
goto done;
}
if (rename(tmppath, newpath) == -1) {
if (errno != ENOENT) {
err = got_error_from_errno3("rename", tmppath,
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(tmppath, newpath) == -1) {
err = got_error_from_errno3("rename", tmppath,
newpath);
goto done;
}
}
if (file_renamed) {
err = got_worktree_schedule_delete(worktree, &oldpaths,
0, NULL, patch_delete, pa, repo, 0, 0);
if (err == NULL)
err = got_worktree_schedule_add(worktree, &newpaths,
patch_add, pa, repo, 1);
if (err)
unlink(newpath);
} else if (p->old == NULL) {
err = got_worktree_schedule_add(worktree, &newpaths,
patch_add, pa, repo, 1);
if (err)
unlink(newpath);
} else
err = report_progress(pa, oldpath, newpath, GOT_STATUS_MODIFY,
NULL);
done:
got_pathlist_free(&oldpaths);
got_pathlist_free(&newpaths);
free(parent);
free(template);
if (tmppath != NULL)
unlink(tmppath);
free(tmppath);
return err;
}
const struct got_error *
got_patch(int fd, struct got_worktree *worktree, struct got_repository *repo,
int nop, got_patch_progress_cb progress_cb, void *progress_arg,
got_cancel_cb cancel_cb, void *cancel_arg)
{
const struct got_error *err = NULL;
struct got_fileindex *fileindex = NULL;
char *oldpath, *newpath;
struct imsgbuf *ibuf;
int imsg_fds[2] = {-1, -1};
int 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, 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);
if (err || done)
break;
err = got_worktree_patch_check_path(p.old, p.new, &oldpath,
&newpath, worktree, repo, fileindex);
if (err == NULL)
err = apply_patch(worktree, repo, 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);
}
free(oldpath);
free(newpath);
patch_free(&p);
if (err)
break;
}
done:
if (fileindex)
got_worktree_patch_complete(fileindex);
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;
}
