busybox/libbb/recursive_action.c
Bernhard Reutner-Fischer 3e816c1252 - fold recurse, depthFirst and dereference params into one param flags.
Minor size improvement (-16b for size, -24b according to bloat-o-meter).
2007-03-29 10:30:50 +00:00

126 lines
3.4 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Utility routines.
*
* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include "libbb.h"
#undef DEBUG_RECURS_ACTION
/*
* Walk down all the directories under the specified
* location, and do something (something specified
* by the fileAction and dirAction function pointers).
*
* Unfortunately, while nftw(3) could replace this and reduce
* code size a bit, nftw() wasn't supported before GNU libc 2.1,
* and so isn't sufficiently portable to take over since glibc2.1
* is so stinking huge.
*/
static int true_action(const char *fileName, struct stat *statbuf,
void* userData, int depth)
{
return TRUE;
}
/* fileAction return value of 0 on any file in directory will make
* recursive_action() return 0, but it doesn't stop directory traversal
* (fileAction/dirAction will be called on each file).
*
* if !depthFirst, dirAction return value of 0 (FALSE) or 2 (SKIP)
* prevents recursion into that directory, instead
* recursive_action() returns 0 (if FALSE) or 1 (if SKIP).
*
* followLinks=0/1 differs mainly in handling of links to dirs.
* 0: lstat(statbuf). Calls fileAction on link name even if points to dir.
* 1: stat(statbuf). Calls dirAction and optionally recurse on link to dir.
*/
int recursive_action(const char *fileName,
unsigned flags,
int (*fileAction)(const char *fileName, struct stat *statbuf, void* userData, int depth),
int (*dirAction)(const char *fileName, struct stat *statbuf, void* userData, int depth),
void* userData,
const unsigned depth)
{
struct stat statbuf;
int status;
DIR *dir;
struct dirent *next;
if (!fileAction) fileAction = true_action;
if (!dirAction) dirAction = true_action;
status = (flags & action_followLinks ? stat : lstat)(fileName, &statbuf);
if (status < 0) {
#ifdef DEBUG_RECURS_ACTION
bb_error_msg("status=%d followLinks=%d TRUE=%d",
status, flags & action_followLinks, TRUE);
#endif
goto done_nak_warn;
}
/* If S_ISLNK(m), then we know that !S_ISDIR(m).
* Then we can skip checking first part: if it is true, then
* (!dir) is also true! */
if ( /* (!(flags & action_followLinks) && S_ISLNK(statbuf.st_mode)) || */
!S_ISDIR(statbuf.st_mode)
) {
return fileAction(fileName, &statbuf, userData, depth);
}
/* It's a directory (or a link to one, and followLinks is set) */
if (!(flags & action_recurse)) {
return dirAction(fileName, &statbuf, userData, depth);
}
if (!(flags & action_depthFirst)) {
status = dirAction(fileName, &statbuf, userData, depth);
if (!status) {
goto done_nak_warn;
}
if (status == SKIP)
return TRUE;
}
dir = opendir(fileName);
if (!dir) {
/* findutils-4.1.20 reports this */
/* (i.e. it doesn't silently return with exit code 1) */
/* To trigger: "find -exec rm -rf {} \;" */
goto done_nak_warn;
}
status = TRUE;
while ((next = readdir(dir)) != NULL) {
char *nextFile;
nextFile = concat_subpath_file(fileName, next->d_name);
if (nextFile == NULL)
continue;
/* now descend into it, forcing recursion. */
if (!recursive_action(nextFile, flags | action_recurse,
fileAction, dirAction, userData, depth+1)) {
status = FALSE;
}
free(nextFile);
}
closedir(dir);
if (flags & action_depthFirst &&
!dirAction(fileName, &statbuf, userData, depth)) {
goto done_nak_warn;
}
if (!status)
return FALSE;
return TRUE;
done_nak_warn:
bb_perror_msg("%s", fileName);
return FALSE;
}