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-rw-r--r--toys/posix/patch.c412
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diff --git a/toys/posix/patch.c b/toys/posix/patch.c
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--- /dev/null
+++ b/toys/posix/patch.c
@@ -0,0 +1,412 @@
+/* vi: set sw=4 ts=4:
+ *
+ * patch.c - Apply a "universal" diff.
+ *
+ * Copyright 2007 Rob Landley <rob@landley.net>
+ *
+ * see http://www.opengroup.org/onlinepubs/009695399/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
+ * -o outfile output here instead of in place
+ * -r rejectfile write rejected hunks to this file
+ *
+ * -E remove empty files --remove-empty-files
+ * -f force (no questions asked)
+ * -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))
+
+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.
+*/
+
+#include "toys.h"
+
+DEFINE_GLOBALS(
+ char *infile;
+ long prefix;
+
+ 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
+// state = 2: write whole line to stderr
+// 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;
+
+ 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);
+ }
+
+ if (PATCH_DEBUG) fprintf(stderr, "DO %d: %s\n", TT.state, dlist->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;
+}
+
+static void fail_hunk(void)
+{
+ if (!TT.current_hunk) return;
+ TT.current_hunk->prev->next = 0;
+
+ 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.
+
+ 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;
+}
+
+// Given a hunk of a unified diff, make the appropriate change to the file.
+// This does not use the location information, but instead treats a hunk
+// as a sort of regex. Copies data from input to output until it finds
+// the change to be made, then outputs the changed data and returns.
+// (Finding EOF first is an error.) This is a single pass operation, so
+// multiple hunks must occur in order in the file.
+
+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;
+ }
+ }
+ }
+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;
+done:
+ if (buf) {
+ buf->prev->next = NULL;
+ llist_traverse(buf, do_line);
+ }
+
+ return TT.state;
+}
+
+// Read a patch file and find hunks, opening/creating/deleting files.
+// Call apply_one_hunk() on each hunk.
+
+// state 0: Not in a hunk, look for +++.
+// state 1: Found +++ file indicator, look for @@
+// state 2: In hunk: counting initial context lines
+// state 3: In hunk: getting body
+
+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);
+ }
+}
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