1/* vi: set sw=4 ts=4: */ 2/* 3 * Utility routines. 4 * 5 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org> 6 * 7 * Licensed under GPLv2 or later, see file LICENSE in this source tree. 8 */ 9#include "libbb.h" 10 11#undef DEBUG_RECURS_ACTION 12 13/* 14 * Walk down all the directories under the specified 15 * location, and do something (something specified 16 * by the fileAction and dirAction function pointers). 17 * 18 * Unfortunately, while nftw(3) could replace this and reduce 19 * code size a bit, nftw() wasn't supported before GNU libc 2.1, 20 * and so isn't sufficiently portable to take over since glibc2.1 21 * is so stinking huge. 22 */ 23 24static int FAST_FUNC true_action(const char *fileName UNUSED_PARAM, 25 struct stat *statbuf UNUSED_PARAM, 26 void* userData UNUSED_PARAM, 27 int depth UNUSED_PARAM) 28{ 29 return TRUE; 30} 31 32/* fileName is (l)stat'ed (depending on ACTION_FOLLOWLINKS[_L0]). 33 * 34 * If it is a file: fileAction in run on it, its return value is returned. 35 * 36 * In case we are in a recursive invocation (see below): 37 * normally, fileAction should return 1 (TRUE) to indicate that 38 * everything is okay and processing should continue. 39 * fileAction return value of 0 (FALSE) on any file in directory will make 40 * recursive_action() also return 0, but it doesn't stop directory traversal 41 * (fileAction/dirAction will be called on each file). 42 * 43 * [TODO: maybe introduce -1 to mean "stop traversal NOW and return"] 44 * 45 * If it is a directory: 46 * 47 * If !ACTION_RECURSE, dirAction is called and its 48 * return value is returned from recursive_action(). No recursion. 49 * 50 * If ACTION_RECURSE, directory is opened, and recursive_action() is called 51 * on each file/subdirectory. 52 * If any one of these calls returns 0, current recursive_action() returns 0. 53 * 54 * If !ACTION_DEPTHFIRST, dirAction is called before recurse. 55 * Return value of 0 (FALSE) is an error: prevents recursion, 56 * the warning is printed (unless ACTION_QUIET) and recursive_action() returns 0. 57 * Return value of 2 (SKIP) prevents recursion, instead recursive_action() 58 * returns 1 (TRUE, no error). 59 * 60 * If ACTION_DEPTHFIRST, dirAction is called after recurse. 61 * If it returns 0, the warning is printed and recursive_action() returns 0. 62 * 63 * ACTION_FOLLOWLINKS mainly controls handling of links to dirs. 64 * 0: lstat(statbuf). Calls fileAction on link name even if points to dir. 65 * 1: stat(statbuf). Calls dirAction and optionally recurse on link to dir. 66 */ 67 68int FAST_FUNC recursive_action(const char *fileName, 69 unsigned flags, 70 int FAST_FUNC (*fileAction)(const char *fileName, struct stat *statbuf, void* userData, int depth), 71 int FAST_FUNC (*dirAction)(const char *fileName, struct stat *statbuf, void* userData, int depth), 72 void* userData, 73 unsigned depth) 74{ 75 struct stat statbuf; 76 unsigned follow; 77 int status; 78 DIR *dir; 79 struct dirent *next; 80 81 if (!fileAction) fileAction = true_action; 82 if (!dirAction) dirAction = true_action; 83 84 follow = ACTION_FOLLOWLINKS; 85 if (depth == 0) 86 follow = ACTION_FOLLOWLINKS | ACTION_FOLLOWLINKS_L0; 87 follow &= flags; 88 status = (follow ? stat : lstat)(fileName, &statbuf); 89 if (status < 0) { 90#ifdef DEBUG_RECURS_ACTION 91 bb_error_msg("status=%d flags=%x", status, flags); 92#endif 93 if ((flags & ACTION_DANGLING_OK) 94 && errno == ENOENT 95 && lstat(fileName, &statbuf) == 0 96 ) { 97 /* Dangling link */ 98 return fileAction(fileName, &statbuf, userData, depth); 99 } 100 goto done_nak_warn; 101 } 102 103 /* If S_ISLNK(m), then we know that !S_ISDIR(m). 104 * Then we can skip checking first part: if it is true, then 105 * (!dir) is also true! */ 106 if ( /* (!(flags & ACTION_FOLLOWLINKS) && S_ISLNK(statbuf.st_mode)) || */ 107 !S_ISDIR(statbuf.st_mode) 108 ) { 109 return fileAction(fileName, &statbuf, userData, depth); 110 } 111 112 /* It's a directory (or a link to one, and followLinks is set) */ 113 114 if (!(flags & ACTION_RECURSE)) { 115 return dirAction(fileName, &statbuf, userData, depth); 116 } 117 118 if (!(flags & ACTION_DEPTHFIRST)) { 119 status = dirAction(fileName, &statbuf, userData, depth); 120 if (status == FALSE) 121 goto done_nak_warn; 122 if (status == SKIP) 123 return TRUE; 124 } 125 126 dir = opendir(fileName); 127 if (!dir) { 128 /* findutils-4.1.20 reports this */ 129 /* (i.e. it doesn't silently return with exit code 1) */ 130 /* To trigger: "find -exec rm -rf {} \;" */ 131 goto done_nak_warn; 132 } 133 status = TRUE; 134 while ((next = readdir(dir)) != NULL) { 135 char *nextFile; 136 int s; 137 138 nextFile = concat_subpath_file(fileName, next->d_name); 139 if (nextFile == NULL) 140 continue; 141 142 /* process every file (NB: ACTION_RECURSE is set in flags) */ 143 s = recursive_action(nextFile, flags, fileAction, dirAction, 144 userData, depth + 1); 145 if (s == FALSE) 146 status = FALSE; 147 free(nextFile); 148//#define RECURSE_RESULT_ABORT -1 149// if (s == RECURSE_RESULT_ABORT) { 150// closedir(dir); 151// return s; 152// } 153 } 154 closedir(dir); 155 156 if (flags & ACTION_DEPTHFIRST) { 157 if (!dirAction(fileName, &statbuf, userData, depth)) 158 goto done_nak_warn; 159 } 160 161 return status; 162 163 done_nak_warn: 164 if (!(flags & ACTION_QUIET)) 165 bb_simple_perror_msg(fileName); 166 return FALSE; 167} 168