From 42ecbab08101d713f9bcd8a107b60338bebb7299 Mon Sep 17 00:00:00 2001 From: Rob Landley Date: Tue, 18 Dec 2007 02:02:21 -0600 Subject: Patch command. --- toys/patch.c | 224 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ toys/toylist.h | 6 +- 2 files changed, 227 insertions(+), 3 deletions(-) create mode 100644 toys/patch.c (limited to 'toys') diff --git a/toys/patch.c b/toys/patch.c new file mode 100644 index 00000000..1ad983c4 --- /dev/null +++ b/toys/patch.c @@ -0,0 +1,224 @@ +/* vi: set sw=4 ts=4: */ +/* + * patch.c - Apply a "universal" diff. + * + * SUSv3 at http://www.opengroup.org/onlinepubs/009695399/utilities/patch.html + * but who cares about "ed"? + * + * -u ignored + * -R reverse (remove applied hunks, apply removed hunks) + * -p num remove this many slashes from start of path (default = all) + * + * 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 + * -i patchfile apply patch from filename rather than stdin + * -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 + */ + +#include "toys.h" + +#define TT toy.patch + +#define FLAG_REVERSE 1 +#define FLAG_PATHLEN 4 + +static void do_line(void *data) +{ + struct double_list *dlist = (struct double_list *)data; + + if (TT.state && *dlist->data != TT.state) + fdprintf(TT.fileout, "%s\n", dlist->data+(TT.state>1 ? 1 : 0)); + free(dlist->data); + free(dlist); +} + + +static void dlist_add(struct double_list **list, char *data) +{ + struct double_list *line = xmalloc(sizeof(struct double_list)); + + line->data = data; + if (*list) { + line->next = *list; + line->prev = (*list)->prev; + (*list)->prev->next = line; + (*list)->prev = line; + } else *list = line->next = line->prev = line; +} + +static void apply_hunk(void) +{ + struct double_list *plist, *temp, *buf; + int i = 0, backwards = 0, reverse = toys.optflags & FLAG_REVERSE; + + TT.state = 0; + + if (!TT.plines) return; + temp = buf = NULL; + + // Hunk is complete, break doubly linked list so we can use singly linked + // traversal function. + TT.plines->prev->next = NULL; + + // Trim extra context lines, if any. If there aren't as many ending + // context lines as beginning lines, this isn't a valid hunk. + for (plist = TT.plines; plist; plist = plist->next) { + if (plist->data[0]==' ') { + if (inext, do_line); + temp->next = NULL; + + // Search for a place to apply this hunk + plist = TT.plines; + buf = NULL; + i = 0; + for (;;) { + char *data = get_line(TT.filein); + TT.linenum++; + + // If the file ended before we found a home for this hunk, fail. + if (!data) break; + + dlist_add(&buf, data); + if (!backwards && *plist->data == "+-"[reverse]) { + backwards = 1; + if (!strcmp(data, plist->data+1)) + fdprintf(1,"Possibly reversed hunk at %ld\n", TT.linenum); + } + while (*plist->data == "+-"[reverse]) plist = plist->next; + if (strcmp(data, plist->data+1)) { // Ignore whitespace? + // Hunk doesn't go here, flush accumulated buffer so far. + + buf->prev->next = NULL; + TT.state = 1; + llist_free(buf, do_line); + buf = NULL; + plist = TT.plines; + } else { + plist = plist->next; + if (!plist) { + // Got it. Emit changed data. + TT.state = "-+"[reverse]; + llist_free(TT.plines, do_line); + TT.plines = NULL; + buf->prev->next = NULL; + TT.state = 0; + llist_free(buf, do_line); + return; + } + } + } +fail_hunk: + printf("Hunk FAILED.\n"); + + // If we got to this point, we've seeked to the end. Discard changes to + // this file and advance to next file. + + TT.state = 0; + llist_free(TT.plines, do_line); + TT.plines = 0; + if (buf) { + buf->prev->next = NULL; + llist_free(buf, do_line); + } + delete_tempfile(TT.filein, TT.fileout, &TT.tempfile); + TT.filein = -1; +} + +// 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) +{ + if (TT.infile) TT.filepatch = xopen(TT.infile, O_RDONLY); + else TT.filepatch = 0; + TT.filein = TT.fileout = -1; + + // Loop through the lines in the patch + for(;;) { + char *patchline; + + patchline = get_line(TT.filepatch); + if (!patchline) break; + + // Are we processing a hunk? + if (TT.state >= 2) { + // Context line? + if (*patchline==' ' || *patchline=='+' || *patchline=='-') { + dlist_add(&TT.plines, patchline); + + if (*patchline==' ' && TT.state==2) TT.context++; + else TT.state=3; + + continue; + } + } + + // If we have a hunk at this point, it's ready to apply. + apply_hunk(); + + // Open a new file? + if (!strncmp("+++ ", patchline, 4)) { + int i; + char *s, *start; + + // Finish old file. + if (TT.tempfile) + replace_tempfile(TT.filein, TT.fileout, &TT.tempfile); + + // 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++; + *s = i = 0; + for (s = start = patchline+4; *s;) { + if ((toys.optflags & FLAG_PATHLEN) && TT.prefix == i) break; + if (*(s++)=='/') { + start = s; + i++; + } + } + + // If we've got a file to open, do so. + if (!(toys.optflags & FLAG_PATHLEN) || i <= TT.prefix) { + printf("patching %s\n", start); + TT.filein = xopen(start, O_RDWR); + TT.fileout = copy_tempfile(TT.filein, start, &TT.tempfile); + TT.state = 1; + TT.context = 0; + TT.linenum = 0; + } + + // Start a new hunk? + } else if (TT.filein!=-1 && !strncmp("@@ ", patchline, 3)) { + TT.context = 0; + TT.state = 2; + sscanf(patchline+3, "%ld,%ld %ld,%ld", &TT.oldline, + &TT.oldlen, &TT.newline, &TT.newlen); + continue; + } + + // This line is noise, discard it. + free(patchline); + } + + // Flush pending hunk and flush data + apply_hunk(); + if (TT.tempfile) replace_tempfile(TT.filein, TT.fileout, &TT.tempfile); + close(TT.filepatch); +} diff --git a/toys/toylist.h b/toys/toylist.h index 9b992028..61e89c1c 100644 --- a/toys/toylist.h +++ b/toys/toylist.h @@ -72,9 +72,9 @@ struct patch_data { long prefix; struct double_list *plines, *flines; - long oldline, oldlen, newline, newlen; - int context, state; - int filein, fileout, filepatch; + long oldline, oldlen, newline, newlen, linenum; + int context, state, filein, fileout, filepatch; + char *tempfile; }; struct sleep_data { -- cgit v1.2.3