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Make xopen() skip stdin/stdout/stderr, add xopen_stdio() if you want stdout,
[android-x86/external-toybox.git] / toys / posix / patch.c
index 647bb18..fbad1fb 100644 (file)
@@ -1,15 +1,12 @@
-/* vi: set sw=4 ts=4:
- *
- * patch.c - Apply a "universal" diff.
+/* patch.c - Apply a "universal" diff.
  *
  * Copyright 2007 Rob Landley <rob@landley.net>
  *
- * see http://www.opengroup.org/onlinepubs/009695399/utilities/patch.html
+ * see http://opengroup.org/onlinepubs/9699919799/utilities/patch.html
  * (But only does -u, because who still cares about "ed"?)
  *
  * TODO:
  * -b backup
- * -l treat all whitespace as a single space
  * -N ignore already applied
  * -d chdir first
  * -D define wrap #ifdef and #ifndef around changes
  * -F fuzz (number, default 2)
  * [file] which file to patch
 
-USE_PATCH(NEWTOY(patch, USE_TOYBOX_DEBUG("x")"up#i:R", TOYFLAG_USR|TOYFLAG_BIN))
+USE_PATCH(NEWTOY(patch, "(dry-run)"USE_TOYBOX_DEBUG("x")"d:ulp#i:R", TOYFLAG_USR|TOYFLAG_BIN))
 
 config PATCH
-       bool "patch"
-       default y
-       help
-         usage: patch [-i file] [-p depth] [-Ru]
-
-         Apply a unified diff to one or more files.
-
-         -i    Input file (defaults=stdin)
-         -p    number of '/' to strip from start of file paths (default=all)
-         -R    Reverse patch.
-         -u    Ignored (only handles "unified" diffs)
-
-         This version of patch only handles unified diffs, and only modifies
-         a file when all all hunks to that file apply.  Patch prints failed
-         hunks to stderr, and exits with nonzero status if any hunks fail.
-
-         A file compared against /dev/null (or with a date <= the epoch) is
-         created/deleted as appropriate.
+  bool "patch"
+  default y
+  help
+    usage: patch [-d DIR] [-i file] [-p depth] [-Rlu] [--dry-run]
+
+    Apply a unified diff to one or more files.
+
+    -d modify files in DIR
+    -i Input file (defaults=stdin)
+    -l Loose match (ignore whitespace)
+    -p Number of '/' to strip from start of file paths (default=all)
+    -R Reverse patch.
+    -u Ignored (only handles "unified" diffs)
+    --dry-run Don't change files, just confirm patch applies
+
+    This version of patch only handles unified diffs, and only modifies
+    a file when all all hunks to that file apply.  Patch prints failed
+    hunks to stderr, and exits with nonzero status if any hunks fail.
+
+    A file compared against /dev/null (or with a date <= the epoch) is
+    created/deleted as appropriate.
 */
 
+#define FOR_patch
 #include "toys.h"
 
-DEFINE_GLOBALS(
-       char *infile;
-       long prefix;
+GLOBALS(
+  char *infile;
+  long prefix;
+  char *dir;
 
-       struct double_list *current_hunk;
-       long oldline, oldlen, newline, newlen;
-       long linenum;
-       int context, state, filein, fileout, filepatch, hunknum;
-       char *tempname;
+  struct double_list *current_hunk;
+  long oldline, oldlen, newline, newlen;
+  long linenum;
+  int context, state, filein, fileout, filepatch, hunknum;
+  char *tempname;
 )
 
-#define TT this.patch
-
-#define FLAG_REVERSE 1
-#define FLAG_PATHLEN 4
-
 // Dispose of a line of input, either by writing it out or discarding it.
 
 // state < 2: just free
@@ -69,49 +66,62 @@ DEFINE_GLOBALS(
 // state = 3: write whole line to fileout
 // state > 3: write line+1 to fileout when *line != state
 
-#define PATCH_DEBUG (CFG_TOYBOX_DEBUG && (toys.optflags & 16))
-
 static void do_line(void *data)
 {
-       struct double_list *dlist = (struct double_list *)data;
+  struct double_list *dlist = (struct double_list *)data;
 
-       if (TT.state>1 && *dlist->data != TT.state) {
-               char *s = dlist->data+(TT.state>3 ? 1 : 0);
-               int i = TT.state == 2 ? 2 : TT.fileout;
+  if (TT.state>1 && *dlist->data != TT.state) {
+    char *s = dlist->data+(TT.state>3 ? 1 : 0);
+    int i = TT.state == 2 ? 2 : TT.fileout;
 
-               xwrite(i, s, strlen(s));
-               xwrite(i, "\n", 1);
-       }
+    xwrite(i, s, strlen(s));
+    xwrite(i, "\n", 1);
+  }
 
-       if (PATCH_DEBUG) fprintf(stderr, "DO %d: %s\n", TT.state, dlist->data);
+  if (toys.optflags & FLAG_x)
+    fprintf(stderr, "DO %d: %s\n", TT.state, dlist->data);
 
-       free(dlist->data);
-       free(data);
+  free(dlist->data);
+  free(data);
 }
 
 static void finish_oldfile(void)
 {
-       if (TT.tempname) replace_tempfile(TT.filein, TT.fileout, &TT.tempname);
-       TT.fileout = TT.filein = -1;
+  if (TT.tempname) replace_tempfile(TT.filein, TT.fileout, &TT.tempname);
+  TT.fileout = TT.filein = -1;
 }
 
 static void fail_hunk(void)
 {
-       if (!TT.current_hunk) return;
-       TT.current_hunk->prev->next = 0;
+  if (!TT.current_hunk) return;
 
-       fprintf(stderr, "Hunk %d FAILED %ld/%ld.\n",
-                       TT.hunknum, TT.oldline, TT.newline);
-       toys.exitval = 1;
+  fprintf(stderr, "Hunk %d FAILED %ld/%ld.\n",
+      TT.hunknum, TT.oldline, TT.newline);
+  toys.exitval = 1;
 
-       // If we got to this point, we've seeked to the end.  Discard changes to
-       // this file and advance to next file.
+  // If we got to this point, we've seeked to the end.  Discard changes to
+  // this file and advance to next file.
 
-       TT.state = 2;
-       llist_traverse(TT.current_hunk, do_line);
-       TT.current_hunk = NULL;
-       delete_tempfile(TT.filein, TT.fileout, &TT.tempname);
-       TT.state = 0;
+  TT.state = 2;
+  llist_traverse(TT.current_hunk, do_line);
+  TT.current_hunk = NULL;
+  if (!(toys.optflags & FLAG_dry_run))
+    delete_tempfile(TT.filein, TT.fileout, &TT.tempname);
+  TT.state = 0;
+}
+
+// Compare ignoring whitespace. Just returns 0/1, no > or <
+static int loosecmp(char *aa, char *bb)
+{
+  int a = 0, b = 0;
+
+  for (;;) {
+    while (isspace(aa[a])) a++;
+    while (isspace(bb[b])) b++;
+    if (aa[a] != bb[b]) return 1;
+    if (!aa[a]) return 0;
+    a++, b++;
+  }
 }
 
 // Given a hunk of a unified diff, make the appropriate change to the file.
@@ -123,114 +133,122 @@ static void fail_hunk(void)
 
 static int apply_one_hunk(void)
 {
-       struct double_list *plist, *buf = NULL, *check;
-       int matcheof = 0, reverse = toys.optflags & FLAG_REVERSE, backwarn = 0;
-
-       // Break doubly linked list so we can use singly linked traversal function.
-       TT.current_hunk->prev->next = NULL;
-
-       // Match EOF if there aren't as many ending context lines as beginning
-       for (plist = TT.current_hunk; plist; plist = plist->next) {
-               if (plist->data[0]==' ') matcheof++;
-               else matcheof = 0;
-               if (PATCH_DEBUG) fprintf(stderr, "HUNK:%s\n", plist->data);
-       }
-       matcheof = matcheof < TT.context;
-
-       if (PATCH_DEBUG) fprintf(stderr,"MATCHEOF=%c\n", matcheof ? 'Y' : 'N');
-
-       // Loop through input data searching for this hunk.  Match all context
-       // lines and all lines to be removed until we've found the end of a
-       // complete hunk.
-       plist = TT.current_hunk;
-       buf = NULL;
-       if (TT.context) for (;;) {
-               char *data = get_line(TT.filein);
-
-               TT.linenum++;
-
-               // Figure out which line of hunk to compare with next.  (Skip lines
-               // of the hunk we'd be adding.)
-               while (plist && *plist->data == "+-"[reverse]) {
-                       if (data && !strcmp(data, plist->data+1)) {
-                               if (!backwarn) backwarn = TT.linenum;
-                       }
-                       plist = plist->next;
-               }
-
-               // Is this EOF?
-               if (!data) {
-                       if (PATCH_DEBUG) fprintf(stderr, "INEOF\n");
-
-                       // Does this hunk need to match EOF?
-                       if (!plist && matcheof) break;
-
-                       if (backwarn)
-                               fprintf(stderr, "Possibly reversed hunk %d at %ld\n",
-                                               TT.hunknum, TT.linenum);
-
-                       // File ended before we found a place for this hunk.
-                       fail_hunk();
-                       goto done;
-               } else if (PATCH_DEBUG) fprintf(stderr, "IN: %s\n", data);
-               check = dlist_add(&buf, data);
-
-               // Compare this line with next expected line of hunk.
-               // todo: teach the strcmp() to ignore whitespace.
-
-               // A match can fail because the next line doesn't match, or because
-               // we hit the end of a hunk that needed EOF, and this isn't EOF.
-
-               // If match failed, flush first line of buffered data and
-               // recheck buffered data for a new match until we find one or run
-               // out of buffer.
-
-               for (;;) {
-                       if (!plist || strcmp(check->data, plist->data+1)) {
-                               // Match failed.  Write out first line of buffered data and
-                               // recheck remaining buffered data for a new match.
-       
-                               if (PATCH_DEBUG)
-                                       fprintf(stderr, "NOT: %s\n", plist->data);
-
-                               TT.state = 3;
-                               check = llist_pop(&buf);
-                               check->prev->next = buf;
-                               buf->prev = check->prev;
-                               do_line(check);
-                               plist = TT.current_hunk;
-
-                               // If we've reached the end of the buffer without confirming a
-                               // match, read more lines.
-                               if (check==buf) {
-                                       buf = 0;
-                                       break;
-                               }
-                               check = buf;
-                       } else {
-                               if (PATCH_DEBUG)
-                                       fprintf(stderr, "MAYBE: %s\n", plist->data);
-                               // This line matches.  Advance plist, detect successful match.
-                               plist = plist->next;
-                               if (!plist && !matcheof) goto out;
-                               check = check->next;
-                               if (check == buf) break;
-                       }
-               }
-       }
+  struct double_list *plist, *buf = NULL, *check;
+  int matcheof, trailing = 0, reverse = toys.optflags & FLAG_R, backwarn = 0;
+  int (*lcmp)(char *aa, char *bb);
+
+  lcmp = (toys.optflags & FLAG_l) ? (void *)loosecmp : (void *)strcmp;
+  dlist_terminate(TT.current_hunk);
+
+  // Match EOF if there aren't as many ending context lines as beginning
+  for (plist = TT.current_hunk; plist; plist = plist->next) {
+    if (plist->data[0]==' ') trailing++;
+    else trailing = 0;
+    if (toys.optflags & FLAG_x) fprintf(stderr, "HUNK:%s\n", plist->data);
+  }
+  matcheof = !trailing || trailing < TT.context;
+
+  if (toys.optflags & FLAG_x)
+    fprintf(stderr,"MATCHEOF=%c\n", matcheof ? 'Y' : 'N');
+
+  // Loop through input data searching for this hunk.  Match all context
+  // lines and all lines to be removed until we've found the end of a
+  // complete hunk.
+  plist = TT.current_hunk;
+  buf = NULL;
+
+  for (;;) {
+    char *data = get_line(TT.filein);
+
+    TT.linenum++;
+    // Figure out which line of hunk to compare with next.  (Skip lines
+    // of the hunk we'd be adding.)
+    while (plist && *plist->data == "+-"[reverse]) {
+      if (data && !lcmp(data, plist->data+1)) {
+        if (!backwarn) backwarn = TT.linenum;
+      }
+      plist = plist->next;
+    }
+
+    // Is this EOF?
+    if (!data) {
+      if (toys.optflags & FLAG_x) fprintf(stderr, "INEOF\n");
+
+      // Does this hunk need to match EOF?
+      if (!plist && matcheof) break;
+
+      if (backwarn)
+        fprintf(stderr, "Possibly reversed hunk %d at %ld\n",
+            TT.hunknum, TT.linenum);
+
+      // File ended before we found a place for this hunk.
+      fail_hunk();
+      goto done;
+    } else if (toys.optflags & FLAG_x) fprintf(stderr, "IN: %s\n", data);
+    check = dlist_add(&buf, data);
+
+    // Compare this line with next expected line of hunk.
+
+    // A match can fail because the next line doesn't match, or because
+    // we hit the end of a hunk that needed EOF, and this isn't EOF.
+
+    // If match failed, flush first line of buffered data and
+    // recheck buffered data for a new match until we find one or run
+    // out of buffer.
+
+    for (;;) {
+      if (!plist || lcmp(check->data, plist->data+1)) {
+        // Match failed.  Write out first line of buffered data and
+        // recheck remaining buffered data for a new match.
+
+        if (toys.optflags & FLAG_x) {
+          int bug = 0;
+
+          if (!plist) fprintf(stderr, "NULL plist\n");
+          else {
+            while (plist->data[bug] == check->data[bug]) bug++;
+            fprintf(stderr, "NOT(%d:%d!=%d): %s\n", bug, plist->data[bug],
+              check->data[bug], plist->data);
+          }
+        }
+
+        // If this hunk must match start of file, fail if it didn't.
+        if (!TT.context || trailing>TT.context) {
+          fail_hunk();
+          goto done;
+        }
+
+        TT.state = 3;
+        do_line(check = dlist_pop(&buf));
+        plist = TT.current_hunk;
+
+        // If we've reached the end of the buffer without confirming a
+        // match, read more lines.
+        if (!buf) break;
+        check = buf;
+      } else {
+        if (toys.optflags & FLAG_x) fprintf(stderr, "MAYBE: %s\n", plist->data);
+        // This line matches.  Advance plist, detect successful match.
+        plist = plist->next;
+        if (!plist && !matcheof) goto out;
+        check = check->next;
+        if (check == buf) break;
+      }
+    }
+  }
 out:
-       // We have a match.  Emit changed data.
-       TT.state = "-+"[reverse];
-       llist_traverse(TT.current_hunk, do_line);
-       TT.current_hunk = NULL;
-       TT.state = 1;
+  // We have a match.  Emit changed data.
+  TT.state = "-+"[reverse];
+  llist_traverse(TT.current_hunk, do_line);
+  TT.current_hunk = NULL;
+  TT.state = 1;
 done:
-       if (buf) {
-               buf->prev->next = NULL;
-               llist_traverse(buf, do_line);
-       }
+  if (buf) {
+    dlist_terminate(buf);
+    llist_traverse(buf, do_line);
+  }
 
-       return TT.state;
+  return TT.state;
 }
 
 // Read a patch file and find hunks, opening/creating/deleting files.
@@ -243,170 +261,171 @@ done:
 
 void patch_main(void)
 {
-       int reverse = toys.optflags&FLAG_REVERSE, state = 0, patchlinenum = 0,
-               strip = 0;
-       char *oldname = NULL, *newname = NULL;
-
-       if (TT.infile) TT.filepatch = xopen(TT.infile, O_RDONLY);
-       TT.filein = TT.fileout = -1;
-
-       // Loop through the lines in the patch
-       for (;;) {
-               char *patchline;
-
-               patchline = get_line(TT.filepatch);
-               if (!patchline) break;
-
-               // Other versions of patch accept damaged patches,
-               // so we need to also.
-               if (strip || !patchlinenum++) {
-                       int len = strlen(patchline);
-                       if (patchline[len-1] == '\r') {
-                               if (!strip) fprintf(stderr, "Removing DOS newlines\n");
-                               strip = 1;
-                               patchline[len-1]=0;
-                       }
-               }
-               if (!*patchline) {
-                       free(patchline);
-                       patchline = xstrdup(" ");
-               }
-
-               // Are we assembling a hunk?
-               if (state >= 2) {
-                       if (*patchline==' ' || *patchline=='+' || *patchline=='-') {
-                               dlist_add(&TT.current_hunk, patchline);
-
-                               if (*patchline != '+') TT.oldlen--;
-                               if (*patchline != '-') TT.newlen--;
-
-                               // Context line?
-                               if (*patchline==' ' && state==2) TT.context++;
-                               else state=3;
-
-                               // If we've consumed all expected hunk lines, apply the hunk.
-
-                               if (!TT.oldlen && !TT.newlen) state = apply_one_hunk();
-                               continue;
-                       }
-                       fail_hunk();
-                       state = 0;
-                       continue;
-               }
-
-               // Open a new file?
-               if (!strncmp("--- ", patchline, 4) || !strncmp("+++ ", patchline, 4)) {
-                       char *s, **name = &oldname;
-                       int i;
-
-                       if (*patchline == '+') {
-                               name = &newname;
-                               state = 1;
-                       }
-
-                       free(*name);
-                       finish_oldfile();
-
-                       // Trim date from end of filename (if any).  We don't care.
-                       for (s = patchline+4; *s && *s!='\t'; s++)
-                               if (*s=='\\' && s[1]) s++;
-                       i = atoi(s);
-                       if (i>1900 && i<=1970)
-                               *name = xstrdup("/dev/null");
-                       else {
-                               *s = 0;
-                               *name = xstrdup(patchline+4);
-                       }
-
-                       // We defer actually opening the file because svn produces broken
-                       // patches that don't signal they want to create a new file the
-                       // way the patch man page says, so you have to read the first hunk
-                       // and _guess_.
-
-               // Start a new hunk?  Usually @@ -oldline,oldlen +newline,newlen @@
-               // but a missing ,value means the value is 1.
-               } else if (state == 1 && !strncmp("@@ -", patchline, 4)) {
-                       int i;
-                       char *s = patchline+4;
-
-                       // Read oldline[,oldlen] +newline[,newlen]
-
-                       TT.oldlen = TT.newlen = 1;
-                       TT.oldline = strtol(s, &s, 10);
-                       if (*s == ',') TT.oldlen=strtol(s+1, &s, 10);
-                       TT.newline = strtol(s+2, &s, 10);
-                       if (*s == ',') TT.newlen = strtol(s+1, &s, 10);
-
-                       TT.context = 0;
-                       state = 2;
-
-                       // If this is the first hunk, open the file.
-                       if (TT.filein == -1) {
-                               int oldsum, newsum, del = 0;
-                               char *name;
-
-                               oldsum = TT.oldline + TT.oldlen;
-                               newsum = TT.newline + TT.newlen;
-
-                               name = reverse ? oldname : newname;
-
-                               // We're deleting oldname if new file is /dev/null (before -p)
-                               // or if new hunk is empty (zero context) after patching
-                               if (!strcmp(name, "/dev/null") || !(reverse ? oldsum : newsum))
-                               {
-                                       name = reverse ? newname : oldname;
-                                       del++;
-                               }
-
-                               // handle -p path truncation.
-                               for (i = 0, s = name; *s;) {
-                                       if ((toys.optflags & FLAG_PATHLEN) && TT.prefix == i) break;
-                                       if (*s++ != '/') continue;
-                                       while (*s == '/') s++;
-                                       name = s;
-                                       i++;
-                               }
-
-                               if (del) {
-                                       printf("removing %s\n", name);
-                                       xunlink(name);
-                                       state = 0;
-                               // If we've got a file to open, do so.
-                               } else if (!(toys.optflags & FLAG_PATHLEN) || i <= TT.prefix) {
-                                       // If the old file was null, we're creating a new one.
-                                       if (!strcmp(oldname, "/dev/null") || !oldsum) {
-                                               printf("creating %s\n", name);
-                                               s = strrchr(name, '/');
-                                               if (s) {
-                                                       *s = 0;
-                                                       xmkpath(name, -1);
-                                                       *s = '/';
-                                               }
-                                               TT.filein = xcreate(name, O_CREAT|O_EXCL|O_RDWR, 0666);
-                                       } else {
-                                               printf("patching %s\n", name);
-                                               TT.filein = xopen(name, O_RDWR);
-                                       }
-                                       TT.fileout = copy_tempfile(TT.filein, name, &TT.tempname);
-                                       TT.linenum = 0;
-                                       TT.hunknum = 0;
-                               }
-                       }
-
-                       TT.hunknum++;
-
-                       continue;
-               }
-
-               // If we didn't continue above, discard this line.
-               free(patchline);
-       }
-
-       finish_oldfile();
-
-       if (CFG_TOYBOX_FREE) {
-               close(TT.filepatch);
-               free(oldname);
-               free(newname);
-       }
+  int reverse = toys.optflags&FLAG_R, state = 0, patchlinenum = 0,
+    strip = 0;
+  char *oldname = NULL, *newname = NULL;
+
+  if (TT.infile) TT.filepatch = xopenro(TT.infile);
+  TT.filein = TT.fileout = -1;
+
+  if (TT.dir) xchdir(TT.dir);
+
+  // Loop through the lines in the patch
+  for (;;) {
+    char *patchline;
+
+    patchline = get_line(TT.filepatch);
+    if (!patchline) break;
+
+    // Other versions of patch accept damaged patches,
+    // so we need to also.
+    if (strip || !patchlinenum++) {
+      int len = strlen(patchline);
+      if (patchline[len-1] == '\r') {
+        if (!strip) fprintf(stderr, "Removing DOS newlines\n");
+        strip = 1;
+        patchline[len-1]=0;
+      }
+    }
+    if (!*patchline) {
+      free(patchline);
+      patchline = xstrdup(" ");
+    }
+
+    // Are we assembling a hunk?
+    if (state >= 2) {
+      if (*patchline==' ' || *patchline=='+' || *patchline=='-') {
+        dlist_add(&TT.current_hunk, patchline);
+
+        if (*patchline != '+') TT.oldlen--;
+        if (*patchline != '-') TT.newlen--;
+
+        // Context line?
+        if (*patchline==' ' && state==2) TT.context++;
+        else state=3;
+
+        // If we've consumed all expected hunk lines, apply the hunk.
+
+        if (!TT.oldlen && !TT.newlen) state = apply_one_hunk();
+        continue;
+      }
+      dlist_terminate(TT.current_hunk);
+      fail_hunk();
+      state = 0;
+      continue;
+    }
+
+    // Open a new file?
+    if (!strncmp("--- ", patchline, 4) || !strncmp("+++ ", patchline, 4)) {
+      char *s, **name = &oldname;
+      int i;
+
+      if (*patchline == '+') {
+        name = &newname;
+        state = 1;
+      }
+
+      free(*name);
+      finish_oldfile();
+
+      // Trim date from end of filename (if any).  We don't care.
+      for (s = patchline+4; *s && *s!='\t'; s++)
+        if (*s=='\\' && s[1]) s++;
+      i = atoi(s);
+      if (i>1900 && i<=1970) *name = xstrdup("/dev/null");
+      else {
+        *s = 0;
+        *name = xstrdup(patchline+4);
+      }
+
+      // We defer actually opening the file because svn produces broken
+      // patches that don't signal they want to create a new file the
+      // way the patch man page says, so you have to read the first hunk
+      // and _guess_.
+
+    // Start a new hunk?  Usually @@ -oldline,oldlen +newline,newlen @@
+    // but a missing ,value means the value is 1.
+    } else if (state == 1 && !strncmp("@@ -", patchline, 4)) {
+      int i;
+      char *s = patchline+4;
+
+      // Read oldline[,oldlen] +newline[,newlen]
+
+      TT.oldlen = TT.newlen = 1;
+      TT.oldline = strtol(s, &s, 10);
+      if (*s == ',') TT.oldlen=strtol(s+1, &s, 10);
+      TT.newline = strtol(s+2, &s, 10);
+      if (*s == ',') TT.newlen = strtol(s+1, &s, 10);
+
+      TT.context = 0;
+      state = 2;
+
+      // If this is the first hunk, open the file.
+      if (TT.filein == -1) {
+        int oldsum, newsum, del = 0;
+        char *name;
+
+        oldsum = TT.oldline + TT.oldlen;
+        newsum = TT.newline + TT.newlen;
+
+        name = reverse ? oldname : newname;
+
+        // We're deleting oldname if new file is /dev/null (before -p)
+        // or if new hunk is empty (zero context) after patching
+        if (!strcmp(name, "/dev/null") || !(reverse ? oldsum : newsum))
+        {
+          name = reverse ? newname : oldname;
+          del++;
+        }
+
+        // handle -p path truncation.
+        for (i = 0, s = name; *s;) {
+          if ((toys.optflags & FLAG_p) && TT.prefix == i) break;
+          if (*s++ != '/') continue;
+          while (*s == '/') s++;
+          name = s;
+          i++;
+        }
+
+        if (del) {
+          printf("removing %s\n", name);
+          xunlink(name);
+          state = 0;
+        // If we've got a file to open, do so.
+        } else if (!(toys.optflags & FLAG_p) || i <= TT.prefix) {
+          // If the old file was null, we're creating a new one.
+          if ((!strcmp(oldname, "/dev/null") || !oldsum) && access(name, F_OK))
+          {
+            printf("creating %s\n", name);
+            if (mkpathat(AT_FDCWD, name, 0, 2))
+              perror_exit("mkpath %s", name);
+            TT.filein = xcreate(name, O_CREAT|O_EXCL|O_RDWR, 0666);
+          } else {
+            printf("patching %s\n", name);
+            TT.filein = xopenro(name);
+          }
+          if (toys.optflags & FLAG_dry_run)
+            TT.fileout = xopen("/dev/null", O_RDWR);
+          else TT.fileout = copy_tempfile(TT.filein, name, &TT.tempname);
+          TT.linenum = 0;
+          TT.hunknum = 0;
+        }
+      }
+
+      TT.hunknum++;
+
+      continue;
+    }
+
+    // If we didn't continue above, discard this line.
+    free(patchline);
+  }
+
+  finish_oldfile();
+
+  if (CFG_TOYBOX_FREE) {
+    close(TT.filepatch);
+    free(oldname);
+    free(newname);
+  }
 }