From 400ff226c2e20486b16759a7351ebf678ac327cf Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sun, 21 Nov 2010 05:54:28 +0100 Subject: patch: simplify double list helpers function old new delta dlist_free - 29 +29 fail_hunk 130 132 +2 patch_main 1987 1982 -5 dlist_add 59 54 -5 TOY_llist_pop 9 - -9 TOY_llist_free 54 - -54 ------------------------------------------------------------------------------ (add/remove: 1/2 grow/shrink: 1/2 up/down: 31/-73) Total: -42 bytes Signed-off-by: Denys Vlasenko --- editors/patch.c | 74 +++++++++++++++++++++++++-------------------------------- 1 file changed, 32 insertions(+), 42 deletions(-) (limited to 'editors') diff --git a/editors/patch.c b/editors/patch.c index 4fadbb8fe..1d4a2554e 100644 --- a/editors/patch.c +++ b/editors/patch.c @@ -56,75 +56,64 @@ #include "libbb.h" + +// libbb candidate? + struct double_list { struct double_list *next; struct double_list *prev; char *data; }; -// Return the first item from the list, advancing the list (which must be called -// as &list) -static -void *TOY_llist_pop(void *list) -{ - // I'd use a void ** for the argument, and even accept the typecast in all - // callers as documentation you need the &, except the stupid compiler - // would then scream about type-punned pointers. Screw it. - void **llist = (void **)list; - void **next = (void **)*llist; - *llist = *next; - - return (void *)next; -} - // Free all the elements of a linked list -// if freeit!=NULL call freeit() on each element before freeing it. +// Call freeit() on each element before freeing it. static -void TOY_llist_free(void *list, void (*freeit)(void *data)) +void dlist_free(struct double_list *list, void (*freeit)(void *data)) { while (list) { - void *pop = TOY_llist_pop(&list); - if (freeit) freeit(pop); - else free(pop); - - // End doubly linked list too. - if (list==pop) break; + void *pop = list; + list = list->next; + freeit(pop); + // Bail out also if list is circular. + if (list == pop) break; } } -//Override bbox's names -#define llist_pop TOY_llist_pop -#define llist_free TOY_llist_free -// Add an entry to the end off a doubly linked list +// Add an entry before "list" element in (circular) doubly linked list static struct double_list *dlist_add(struct double_list **list, char *data) { - struct double_list *line = xmalloc(sizeof(struct double_list)); + struct double_list *llist; + struct double_list *line = xmalloc(sizeof(*line)); 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; + llist = *list; + if (llist) { + struct double_list *p; + line->next = llist; + p = line->prev = llist->prev; + // (list is circular, we assume p is never NULL) + p->next = line; + llist->prev = line; + } else + *list = line->next = line->prev = line; return line; } - struct globals { char *infile; long prefix; struct double_list *current_hunk; + long oldline, oldlen, newline, newlen; long linenum; - int context, state, filein, fileout, hunknum; + int context, state, hunknum; + int filein, fileout; char *tempname; - // was toys.foo: int exitval; }; #define TT (*ptr_to_globals) @@ -193,7 +182,6 @@ static void finish_oldfile(void) static void fail_hunk(void) { if (!TT.current_hunk) return; - TT.current_hunk->prev->next = NULL; fdprintf(2, "Hunk %d FAILED %ld/%ld.\n", TT.hunknum, TT.oldline, TT.newline); TT.exitval = 1; @@ -202,7 +190,8 @@ static void fail_hunk(void) // this file and advance to next file. TT.state = 2; - llist_free(TT.current_hunk, do_line); + TT.current_hunk->prev->next = NULL; + dlist_free(TT.current_hunk, do_line); TT.current_hunk = NULL; // Abort the copy and delete the temporary file. @@ -308,7 +297,8 @@ static int apply_one_hunk(void) fdprintf(2, "NOT: %s\n", plist->data); TT.state = 3; - check = llist_pop(&buf); + check = buf; + buf = buf->next; check->prev->next = buf; buf->prev = check->prev; do_line(check); @@ -335,13 +325,13 @@ static int apply_one_hunk(void) out: // We have a match. Emit changed data. TT.state = "-+"[reverse ^ dummy_revert]; - llist_free(TT.current_hunk, do_line); + dlist_free(TT.current_hunk, do_line); TT.current_hunk = NULL; TT.state = 1; done: if (buf) { buf->prev->next = NULL; - llist_free(buf, do_line); + dlist_free(buf, do_line); } return TT.state; -- cgit v1.2.3