aboutsummaryrefslogtreecommitdiff
path: root/toys/patch.c
diff options
context:
space:
mode:
authorRob Landley <rob@landley.net>2009-11-29 22:14:06 -0600
committerRob Landley <rob@landley.net>2009-11-29 22:14:06 -0600
commit0f01f299acf0109b780dd7e9e3247f5253b6fd2e (patch)
treeec824ce407e2a1f5255351395dc9f84a310004cb /toys/patch.c
parent05e451de7b7fbadff09af6f1117102603181df29 (diff)
downloadtoybox-0f01f299acf0109b780dd7e9e3247f5253b6fd2e.tar.gz
Fix reversed patch detection logic, remove unused variables, rename variables, better comments.
Diffstat (limited to 'toys/patch.c')
-rw-r--r--toys/patch.c73
1 files changed, 40 insertions, 33 deletions
diff --git a/toys/patch.c b/toys/patch.c
index 84e4d197..11b4d8aa 100644
--- a/toys/patch.c
+++ b/toys/patch.c
@@ -50,7 +50,7 @@ DEFINE_GLOBALS(
char *infile;
long prefix;
- struct double_list *plines, *flines;
+ struct double_list *current_hunk;
long oldline, oldlen, newline, newlen, linenum;
int context, state, filein, fileout, filepatch, hunknum;
char *tempname;
@@ -88,18 +88,18 @@ static void finish_oldfile(void)
static void fail_hunk(void)
{
- if (!TT.plines) return;
- TT.plines->prev->next = 0;
+ if (!TT.current_hunk) return;
+ TT.current_hunk->prev->next = 0;
- fdprintf(2, "Hunk %d FAILED.\n", TT.hunknum);
+ fdprintf(2, "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_free(TT.plines, do_line);
- TT.plines = NULL;
+ llist_free(TT.current_hunk, do_line);
+ TT.current_hunk = NULL;
delete_tempfile(TT.filein, TT.fileout, &TT.tempname);
TT.state = 0;
}
@@ -107,38 +107,38 @@ static void fail_hunk(void)
static int apply_hunk(void)
{
struct double_list *plist, *buf = NULL, *check;
- int i = 0, backwards = 0, matcheof = 0,
- reverse = toys.optflags & FLAG_REVERSE;
+ int matcheof = 0, reverse = toys.optflags & FLAG_REVERSE, backwarn = 0;
// Break doubly linked list so we can use singly linked traversal function.
- TT.plines->prev->next = NULL;
+ TT.current_hunk->prev->next = NULL;
// Match EOF if there aren't as many ending context lines as beginning
- for (plist = TT.plines; plist; plist = plist->next) {
- if (plist->data[0]==' ') i++;
- else i = 0;
+ for (plist = TT.current_hunk; plist; plist = plist->next) {
+ if (plist->data[0]==' ') matcheof++;
+ else matcheof = 0;
}
- if (i < TT.context) matcheof++;
+ matcheof = matcheof < TT.context;
- // Search for a place to apply this hunk. Match all context lines and
- // lines to be removed.
- plist = TT.plines;
+ // 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;
- i = 0;
-
- // Start of for loop
if (TT.context) for (;;) {
char *data = get_line(TT.filein);
TT.linenum++;
- // Skip lines of the hunk we'd be adding.
+ // 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 (++backwards == TT.context)
+ if (!backwarn) {
fdprintf(2,"Possibly reversed hunk %d at %ld\n",
TT.hunknum, TT.linenum);
- } else backwards=0;
+ backwarn++;
+ }
+ }
plist = plist->next;
}
@@ -153,23 +153,30 @@ static int apply_hunk(void)
}
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 we hit the end of a hunk that needed EOF and this isn't EOF,
- // or next line doesn't match, flush first line of buffered data and
- // recheck match until we find a new match or run out of buffer.
-
if (!plist || strcmp(check->data, plist->data+1)) {
- // First line isn't a match, write it out.
+ // Match failed. Write out first line of buffered data and
+ // recheck remaining buffered data for a new match.
+
TT.state = 3;
check = llist_pop(&buf);
check->prev->next = buf;
buf->prev = check->prev;
do_line(check);
- plist = TT.plines;
+ plist = TT.current_hunk;
- // Out of buffered lines?
+ // If we've reached the end of the buffer without confirming a
+ // match, read more lines.
if (check==buf) {
buf = 0;
break;
@@ -185,10 +192,10 @@ static int apply_hunk(void)
}
}
out:
- // Got it. Emit changed data.
+ // We have a match. Emit changed data.
TT.state = "-+"[reverse];
- llist_free(TT.plines, do_line);
- TT.plines = NULL;
+ llist_free(TT.current_hunk, do_line);
+ TT.current_hunk = NULL;
TT.state = 1;
done:
if (buf) {
@@ -229,7 +236,7 @@ void patch_main(void)
// Are we assembling a hunk?
if (state >= 2) {
if (*patchline==' ' || *patchline=='+' || *patchline=='-') {
- dlist_add(&TT.plines, patchline);
+ dlist_add(&TT.current_hunk, patchline);
if (*patchline != '+') TT.oldlen--;
if (*patchline != '-') TT.newlen--;