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Diffstat (limited to 'toys/patch.c')
-rw-r--r--toys/patch.c32
1 files changed, 28 insertions, 4 deletions
diff --git a/toys/patch.c b/toys/patch.c
index 58ca5b3f..63599652 100644
--- a/toys/patch.c
+++ b/toys/patch.c
@@ -21,7 +21,7 @@
* -F fuzz (number, default 2)
* [file] which file to patch
-USE_PATCH(NEWTOY(patch, "up#i:R", TOYFLAG_USR|TOYFLAG_BIN))
+USE_PATCH(NEWTOY(patch, USE_TOYBOX_DEBUG("x")"up#i:R", TOYFLAG_USR|TOYFLAG_BIN))
config PATCH
bool "patch"
@@ -68,6 +68,8 @@ 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;
@@ -76,6 +78,8 @@ static void do_line(void *data)
fdprintf(TT.state == 2 ? 2 : TT.fileout,
"%s\n", dlist->data+(TT.state>3 ? 1 : 0));
+ if (PATCH_DEBUG) fdprintf(2, "DO %d: %s\n", TT.state, dlist->data);
+
free(dlist->data);
free(data);
}
@@ -104,7 +108,14 @@ static void fail_hunk(void)
TT.state = 0;
}
-static int apply_hunk(void)
+// 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;
@@ -116,9 +127,12 @@ static int apply_hunk(void)
for (plist = TT.current_hunk; plist; plist = plist->next) {
if (plist->data[0]==' ') matcheof++;
else matcheof = 0;
+ if (PATCH_DEBUG) fdprintf(2, "HUNK:%s\n", plist->data);
}
matcheof = matcheof < TT.context;
+ if (PATCH_DEBUG) fdprintf(2,"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.
@@ -144,13 +158,15 @@ static int apply_hunk(void)
// Is this EOF?
if (!data) {
+ if (PATCH_DEBUG) fdprintf(2, "INEOF\n");
+
// Does this hunk need to match EOF?
if (!plist && matcheof) break;
// File ended before we found a place for this hunk.
fail_hunk();
goto done;
- }
+ } else if (PATCH_DEBUG) fdprintf(2, "IN: %s\n", data);
check = dlist_add(&buf, data);
// Compare this line with next expected line of hunk.
@@ -168,6 +184,9 @@ static int apply_hunk(void)
// Match failed. Write out first line of buffered data and
// recheck remaining buffered data for a new match.
+ if (PATCH_DEBUG)
+ fdprintf(2, "NOT: %s\n", plist->data);
+
TT.state = 3;
check = llist_pop(&buf);
check->prev->next = buf;
@@ -183,6 +202,8 @@ static int apply_hunk(void)
}
check = buf;
} else {
+ if (PATCH_DEBUG)
+ fdprintf(2, "MAYBE: %s\n", plist->data);
// This line matches. Advance plist, detect successful match.
plist = plist->next;
if (!plist && !matcheof) goto out;
@@ -206,6 +227,9 @@ done:
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
@@ -247,7 +271,7 @@ void patch_main(void)
// If we've consumed all expected hunk lines, apply the hunk.
- if (!TT.oldlen && !TT.newlen) state = apply_hunk();
+ if (!TT.oldlen && !TT.newlen) state = apply_one_hunk();
continue;
}
fail_hunk();