From a6b5b60942b4e28965f10cb107d4f94aaf756bc1 Mon Sep 17 00:00:00 2001 From: Rob Landley Date: Mon, 8 May 2006 19:03:07 +0000 Subject: [PATCH] Fiddling with llist to make memory management easier. Specifically, the option to delete the contents of the list when we delete the list is a good thing. --- include/libbb.h | 4 ++-- libbb/Makefile.in | 2 +- libbb/llist.c | 31 +++++++++++++++++++++---------- procps/pidof.c | 4 ++-- util-linux/mount.c | 2 +- 5 files changed, 27 insertions(+), 16 deletions(-) diff --git a/include/libbb.h b/include/libbb.h index 48239798b..39361a232 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -477,8 +477,8 @@ typedef struct llist_s { } llist_t; extern llist_t *llist_add_to(llist_t *old_head, char *new_item); extern llist_t *llist_add_to_end(llist_t *list_head, char *data); -extern llist_t *llist_free_one(llist_t *elm); -extern void llist_free(llist_t *elm); +extern void *llist_pop(llist_t **elm); +extern void llist_free(llist_t *elm, void (*freeit)(void *data)); extern void print_login_issue(const char *issue_file, const char *tty); extern void print_login_prompt(void); diff --git a/libbb/Makefile.in b/libbb/Makefile.in index e7725b8f0..865b7e726 100644 --- a/libbb/Makefile.in +++ b/libbb/Makefile.in @@ -101,7 +101,7 @@ $(LIBBB_MOBJ5):$(LIBBB_MSRC5) $(compile.c) -DL_$(notdir $*) LIBBB_MSRC6:=$(srcdir)/llist.c -LIBBB_MOBJ6:=llist_add_to.o llist_add_to_end.o llist_free_one.o llist_free.o +LIBBB_MOBJ6:=llist_add_to.o llist_add_to_end.o llist_pop.o llist_free.o LIBBB_MOBJ6:=$(patsubst %,$(LIBBB_DIR)/%, $(LIBBB_MOBJ6)) $(LIBBB_MOBJ6):$(LIBBB_MSRC6) $(compile.c) -DL_$(notdir $*) diff --git a/libbb/llist.c b/libbb/llist.c index 5b70d6628..0d599db6b 100644 --- a/libbb/llist.c +++ b/libbb/llist.c @@ -47,21 +47,32 @@ llist_t *llist_add_to_end(llist_t *list_head, char *data) } #endif -#ifdef L_llist_free_one -/* Free the current list element and advance to the next entry in the list. - * Returns a pointer to the next element. */ -llist_t *llist_free_one(llist_t *elm) +#ifdef L_llist_pop +/* Remove first element from the list and return it */ +void *llist_pop(llist_t **head) { - llist_t *next = elm ? elm->link : NULL; - free(elm); - return next; + void *data; + + if(!*head) data = *head; + else { + void *next = (*head)->link; + data = (*head)->data; + *head = (*head)->link; + free(next); + } + + return data; } #endif #ifdef L_llist_free -/* Recursively free all elements in the linked list. */ -void llist_free(llist_t *elm) +/* Recursively free all elements in the linked list. If freeit != NULL + * call it on each datum in the list */ +void llist_free(llist_t *elm, void (*freeit)(void *data)) { - while ((elm = llist_free_one(elm))); + while (elm) { + void *data = llist_pop(&elm); + if (freeit) freeit(data); + } } #endif diff --git a/procps/pidof.c b/procps/pidof.c index 5b3e53fdf..98008aaf1 100644 --- a/procps/pidof.c +++ b/procps/pidof.c @@ -65,7 +65,7 @@ int pidof_main(int argc, char **argv) while (omits_p) { /* are we asked to exclude the parent's process ID? */ if (!strncmp(omits_p->data, "%PPID", 5)) { - omits_p = llist_free_one(omits_p); + llist_pop(&omits_p); snprintf(getppid_str, sizeof(getppid_str), "%d", getppid()); omits_p = llist_add_to(omits_p, getppid_str); #if 0 @@ -117,7 +117,7 @@ int pidof_main(int argc, char **argv) #if ENABLE_FEATURE_PIDOF_OMIT if (ENABLE_FEATURE_CLEAN_UP) - llist_free(omits); + llist_free(omits, NULL); #endif return fail ? EXIT_FAILURE : EXIT_SUCCESS; } diff --git a/util-linux/mount.c b/util-linux/mount.c index 61ceba829..4bd6433ca 100644 --- a/util-linux/mount.c +++ b/util-linux/mount.c @@ -182,7 +182,7 @@ llist_t *fslist = 0; #if ENABLE_FEATURE_CLEAN_UP static void delete_block_backed_filesystems(void) { - llist_free(fslist); + llist_free(fslist, free); } #else void delete_block_backed_filesystems(void);