+++ /dev/null
-/* $Id: fastrm.c 6155 2003-01-19 19:58:25Z rra $
-**
-** Delete a list of filenames or tokens from stdin.
-**
-** Originally written by <kre@munnari.oz.au> (to only handle files)
-**
-** Files that can't be unlinked because they didn't exist are considered
-** okay. Any error condition results in exiting with non-zero exit
-** status. Input lines in the form @...@ are taken to be storage API
-** tokens. Input filenames should be fully qualified. For maximum
-** efficiency, input filenames should be sorted; fastrm will cd into each
-** directory to avoid additional directory lookups when removing a lot of
-** files in a single directory.
-*/
-
-#include "config.h"
-#include "clibrary.h"
-#include <ctype.h>
-#include <dirent.h>
-#include <errno.h>
-#include <sys/stat.h>
-#include <syslog.h>
-
-#include "inn/innconf.h"
-#include "inn/messages.h"
-#include "inn/qio.h"
-#include "libinn.h"
-#include "storage.h"
-
-/* We reject any path names longer than this. */
-#define MAX_DIR_LEN 2048
-
-/* Data structure for a list of files in a single directory. */
-typedef struct filelist {
- int count;
- int size;
- char *dir;
- char **files;
-} filelist;
-
-/* All relative paths are relative to this directory. */
-static char *base_dir = NULL;
-
-/* The absolute path of the current working directory. */
-static char current_dir[MAX_DIR_LEN];
-
-/* The prefix for the files that we're currently working with. We sometimes
- also use this as working space for forming file names to remove, so give
- ourselves a bit of additional leeway just in case. */
-static char prefix_dir[MAX_DIR_LEN * 2];
-static int prefix_len;
-
-/* Some threshold values that govern the optimizations that we are willing
- to perform. chdir_threshold determines how many files to be removed we
- want in a directory before we chdir to that directory. sort_threshold
- determines how many files must be in a directory before we use readdir to
- remove them in order. relative_threshold determines how many levels of
- "../" we're willing to try to use to move to the next directory rather
- than just calling chdir with the new absolute path. */
-static int chdir_threshold = 3;
-static int relative_threshold = 0;
-static int sort_threshold = 0;
-
-/* True if we should only print what we would do, not actually do it. */
-static bool debug_only = false;
-
-/* A string used for constructing relative paths. */
-static const char dotdots[] = "../../../../";
-
-/* The number of errors encountered, used to determine exit status. */
-static int error_count = 0;
-
-/* Whether the storage manager has been initialized. */
-static bool sm_initialized = false;
-
-/* True if unlink may be able to remove directories. */
-static bool unlink_dangerous = false;
-
-
-
-/*
-** Sorting predicate for qsort and bsearch.
-*/
-static int
-file_compare(const void *a, const void *b)
-{
- const char *f1, *f2;
-
- f1 = *((const char **) a);
- f2 = *((const char **) b);
- return strcmp(f1, f2);
-}
-
-
-/*
-** Create a new filelist.
-*/
-static filelist *
-filelist_new(char *dir)
-{
- filelist *new;
-
- new = xmalloc(sizeof(filelist));
- new->count = 0;
- new->size = 0;
- new->dir = dir;
- new->files = NULL;
- return new;
-}
-
-
-/*
-** Insert a file name into a list of files (unsorted).
-*/
-static void
-filelist_insert(filelist *list, char *name)
-{
- if (list->count == list->size) {
- list->size = (list->size == 0) ? 16 : list->size * 2;
- list->files = xrealloc(list->files, list->size * sizeof(char *));
- }
- list->files[list->count++] = xstrdup(name);
-}
-
-
-/*
-** Find a file name in a sorted list of files.
-*/
-static char *
-filelist_lookup(filelist *list, const char *name)
-{
- char **p;
-
- p = bsearch(&name, list->files, list->count, sizeof(char *),
- file_compare);
- return (p == NULL ? NULL : *p);
-}
-
-
-/*
-** Empty a list of files, freeing all of the names but keeping the
-** structure intact.
-*/
-static void
-filelist_empty(filelist *list)
-{
- int i;
-
- for (i = 0; i < list->count; i++)
- free(list->files[i]);
- list->count = 0;
-}
-
-
-/*
-** Free a list of files.
-*/
-static void
-filelist_free(filelist *list)
-{
- filelist_empty(list);
- if (list->files != NULL)
- free(list->files);
- if (list->dir != NULL)
- free(list->dir);
- free(list);
-}
-
-
-/*
-** Exit handler for die. Shut down the storage manager before exiting.
-*/
-static int
-sm_cleanup(void)
-{
- SMshutdown();
- return 1;
-}
-
-
-/*
-** Initialize the storage manager. This includes parsing inn.conf, which
-** fastrm doesn't need for any other purpose.
-*/
-static void
-sm_initialize(void)
-{
- bool value;
-
- if (!innconf_read(NULL))
- exit(1);
- value = true;
- if (!SMsetup(SM_RDWR, &value) || !SMsetup(SM_PREOPEN, &value))
- die("can't set up storage manager");
- if (!SMinit())
- die("can't initialize storage manager: %s", SMerrorstr);
- sm_initialized = true;
- message_fatal_cleanup = sm_cleanup;
-}
-
-
-/*
-** Get a line from a given QIO stream, returning a pointer to it. Warn
-** about and then skip lines that are too long. Returns NULL at EOF or on
-** an error.
-*/
-static char *
-get_line(QIOSTATE *qp)
-{
- static int count;
- char *p;
-
- p = QIOread(qp);
- count++;
- while (QIOtoolong(qp) || (p != NULL && strlen(p) >= MAX_DIR_LEN)) {
- warn("line %d too long", count);
- error_count++;
- while (p == NULL && QIOtoolong(qp))
- p = QIOread(qp);
- p = QIOread(qp);
- }
- if (p == NULL) {
- if (QIOerror(qp)) {
- syswarn("read error");
- error_count++;
- }
- return NULL;
- }
- return p;
-}
-
-
-/*
-** Read lines from stdin (including the first that may have been there
-** from our last time in) until we reach EOF or until we get a line that
-** names a file not in the same directory as the previous lot. Remember
-** the file names in the directory we're examining and return the list.
-*/
-static filelist *
-process_line(QIOSTATE *qp, int *queued, int *deleted)
-{
- static char *line = NULL;
- filelist *list = NULL;
- char *p;
- char *dir = NULL;
- int dlen = -1;
-
- *queued = 0;
- *deleted = 0;
-
- if (line == NULL)
- line = get_line(qp);
-
- for (; line != NULL; line = get_line(qp)) {
- if (IsToken(line)) {
- (*deleted)++;
- if (debug_only) {
- printf("Token %s\n", line);
- continue;
- }
- if (!sm_initialized)
- sm_initialize();
- if (!SMcancel(TextToToken(line)))
- if (SMerrno != SMERR_NOENT && SMerrno != SMERR_UNINIT) {
- warn("can't cancel %s", line);
- error_count++;
- }
- } else {
- if (list == NULL) {
- p = strrchr(line, '/');
- if (p != NULL) {
- *p++ = '\0';
- dlen = strlen(line);
- dir = xstrdup(line);
- } else {
- p = line;
- dlen = -1;
- dir = NULL;
- }
- list = filelist_new(dir);
- } else {
- if ((dlen < 0 && strchr(line, '/'))
- || (dlen >= 0 && (line[dlen] != '/'
- || strchr(line + dlen + 1, '/')
- || strncmp(dir, line, dlen))))
- return list;
- }
- filelist_insert(list, line + dlen + 1);
- (*queued)++;
- }
- }
- return list;
-}
-
-
-/*
-** Copy n leading segments of a path.
-*/
-static void
-copy_segments(char *to, const char *from, int n)
-{
- char c;
-
- for (c = *from++; c != '\0'; c = *from++) {
- if (c == '/' && --n <= 0)
- break;
- *to++ = c;
- }
- *to = '\0';
-}
-
-
-/*
-** Return the count of path segments in a file name (the number of
-** slashes).
-*/
-static int
-slashcount(char *name)
-{
- int i;
-
- for (i = 0; *name != '\0'; name++)
- if (*name == '/')
- i++;
- return i;
-}
-
-
-/*
-** Unlink a file, reporting errors if the unlink fails for a reason other
-** than the file not existing doesn't exist. Be careful to avoid unlinking
-** a directory if unlink_dangerous is true.
-*/
-static void
-unlink_file(const char *file)
-{
- struct stat st;
-
- /* On some systems, unlink will remove directories if used by root. If
- we're running as root, unlink_dangerous will be set, and we need to
- make sure that the file isn't a directory first. */
- if (unlink_dangerous) {
- if (stat(file, &st) < 0) {
- if (errno != ENOENT) {
- if (*file == '/')
- syswarn("can't stat %s", file);
- else
- syswarn("can't stat %s in %s", file, current_dir);
- error_count++;
- }
- return;
- }
- if (S_ISDIR(st.st_mode)) {
- if (*file == '/')
- syswarn("%s is a directory", file);
- else
- syswarn("%s in %s is a directory", file, current_dir);
- error_count++;
- return;
- }
- }
-
- if (debug_only) {
- if (*file != '/')
- printf("%s / ", current_dir);
- printf("%s\n", file);
- return;
- }
-
- if (unlink(file) < 0 && errno != ENOENT) {
- if (*file == '/')
- syswarn("can't unlink %s", file);
- else
- syswarn("can't unlink %s in %s", file, current_dir);
- }
-}
-
-
-/*
-** A wrapper around chdir that dies if chdir fails for a reason other than
-** the directory not existing, returns false if the directory doesn't
-** exist (reporting an error), and otherwise returns true. It also checks
-** to make sure that filecount is larger than chdir_threshold, and if it
-** isn't it instead just sets prefix_dir and prefix_len to point to the new
-** directory without changing the working directory.
-*/
-static bool
-chdir_checked(const char *path, int filecount)
-{
- if (filecount < chdir_threshold) {
- strlcpy(prefix_dir, path, sizeof(prefix_dir));
- prefix_len = strlen(path);
- } else {
- prefix_len = 0;
- if (chdir(path) < 0) {
- if (errno != ENOENT)
- sysdie("can't chdir from %s to %s", current_dir, path);
- else {
- syswarn("can't chdir from %s to %s", current_dir, path);
- return false;
- }
- }
- }
- return true;
-}
-
-
-/*
-** Set our environment (process working directory, and global vars) to
-** reflect a change of directory to dir (relative to base_dir if dir is not
-** an absolute path). We're likely to want to do different things
-** depending on the amount of work to do in dir, so we also take the number
-** of files to remove in dir as the second argument. Return false if the
-** directory doesn't exist (and therefore all files in it have already been
-** removed; otherwise, return true.
-*/
-static bool
-setup_dir(char *dir, int filecount)
-{
- char *p, *q, *absolute;
- char path[MAX_DIR_LEN];
- int base_depth, depth;
-
- /* Set absolute to the absolute path to the new directory. */
- if (dir == NULL)
- absolute = base_dir;
- else if (*dir == '/')
- absolute = dir;
- else if (*dir == '\0') {
- strlcpy(path, "/", sizeof(path));
- absolute = path;
- } else {
- /* Strip off leading "./". */
- while (dir[0] == '.' && dir[1] == '/')
- for (dir += 2; *dir == '/'; dir++)
- ;
-
- /* Handle any leading "../", but only up to the number of segments
- in base_dir. */
- base_depth = slashcount(base_dir);
- while (base_depth > 0 && strncmp(dir, "../", 3) == 0)
- for (base_depth--, dir += 3; *dir == '/'; dir++)
- ;
- if (base_depth <= 0)
- die("too many ../'s in path %s", dir);
- copy_segments(path, base_dir, base_depth + 1);
- if (strlen(path) + strlen(dir) + 2 > MAX_DIR_LEN)
- die("path %s too long", dir);
- strlcat(path, "/", sizeof(path));
- strlcat(path, dir, sizeof(path));
- absolute = path;
- }
-
- /* Find the first point of difference between absolute and current_dir.
- If there is no difference, we're done; we're changing to the same
- directory we were in (this is probably some sort of error, but can
- happen with odd relative paths). */
- for (p = absolute, q = current_dir; *p == *q; p++, q++)
- if (*p == '\0')
- return true;
-
- /* If we reached the end of current_dir and there's more left of
- absolute, we're changing to a subdirectory of where we were. */
- if (*q == '\0' && *p == '/') {
- p++;
- if (!chdir_checked(p, filecount))
- return false;
- if (prefix_len == 0)
- strlcpy(current_dir, absolute, sizeof(current_dir));
- return true;
- }
-
- /* Otherwise, if we were promised that we have a pure tree (in other
- words, no symbolic links to directories), see if it's worth going up
- the tree with ".." and then down again rather than chdir to the
- absolute path. relative_threshold determines how many levels of ".."
- we're willing to use; the default of 1 seems fractionally faster than
- 2 and 0 indicates to always use absolute paths. Values larger than 3
- would require extending the dotdots string, but are unlikely to be
- worth it.
-
- FIXME: It's too hard to figure out what this code does. It needs to be
- rewritten. */
- if (p != '\0' && relative_threshold > 0) {
- depth = slashcount(q);
- if (depth <= relative_threshold) {
- while (p > absolute && *--p != '/')
- ;
- p++;
- strlcpy(prefix_dir, dotdots + 9 - depth * 3, sizeof(prefix_dir));
- strlcat(prefix_dir, p, sizeof(prefix_dir));
- if (!chdir_checked(prefix_dir, filecount))
- return false;
-
- /* Now patch up current_dir to reflect where we are. */
- if (prefix_len == 0) {
- while (q > current_dir && *--q != '/')
- ;
- q[1] = '\0';
- strlcat(current_dir, p, sizeof(current_dir));
- }
- return true;
- }
- }
-
- /* All else has failed; just use the absolute path. This includes the
- case where current_dir is a subdirectory of absolute, in which case
- it may be somewhat faster to use chdir("../..") or the like rather
- than the absolute path, but this case rarely happens when the user
- cares about speed (it usually doesn't happen with sorted input). So
- we don't bother. */
- if (!chdir_checked(absolute, filecount))
- return false;
- if (prefix_len == 0)
- strlcpy(current_dir, absolute, sizeof(current_dir));
- return true;
-}
-
-
-/*
-** Process a filelist of files to be deleted, all in the same directory.
-*/
-static void
-unlink_filelist(filelist *list, int filecount)
-{
- bool sorted;
- DIR *dir;
- struct dirent *entry;
- char *file;
- int i;
-
- /* If setup_dir returns false, the directory doesn't exist and we're
- already all done. */
- if (!setup_dir(list->dir, filecount)) {
- filelist_free(list);
- return;
- }
-
- /* We'll use prefix_dir as a buffer to write each file name into as we
- go, so get it set up. */
- if (prefix_len == 0)
- file = prefix_dir;
- else {
- prefix_dir[prefix_len++] = '/';
- file = prefix_dir + prefix_len;
- *file = '\0';
- }
-
- /* If we're not sorting directories or if the number of files is under
- the threshold, just remove the files. */
- if (sort_threshold == 0 || filecount < sort_threshold) {
- for (i = 0; i < list->count; i++) {
- strlcpy(file, list->files[i], sizeof(prefix_dir) - prefix_len);
- unlink_file(prefix_dir);
- }
- filelist_free(list);
- return;
- }
-
- /* We have enough files to remove in this directory that it's worth
- optimizing. First, make sure the list of files is sorted. It's not
- uncommon for the files to already be sorted, so check first. */
- for (sorted = true, i = 1; sorted && i < list->count; i++)
- sorted = (strcmp(list->files[i - 1], list->files[i]) <= 0);
- if (!sorted)
- qsort(list->files, list->count, sizeof(char *), file_compare);
-
- /* Now, begin doing our optimized unlinks. The technique we use is to
- open the directory containing the files and read through it, checking
- each file in the directory to see if it's one of the files we should
- be removing. The theory is that we want to minimize the amount of
- time the operating system spends doing string compares trying to find
- the file to be removed in the directory. This is often an O(n)
- operation. Note that this optimization may slightly slow more
- effecient operating systems. */
- dir = opendir(prefix_len == 0 ? "." : prefix_dir);
- if (dir == NULL) {
- if (prefix_len > 0 && prefix_dir[0] == '/')
- warn("can't open directory %s", prefix_dir);
- else
- warn("can't open directory %s in %s",
- (prefix_len == 0) ? "." : prefix_dir, current_dir);
- error_count++;
- filelist_free(list);
- return;
- }
- for (i = 0, entry = readdir(dir); entry != NULL; entry = readdir(dir))
- if (filelist_lookup(list, entry->d_name) != NULL) {
- i++;
- strlcpy(file, entry->d_name, sizeof(prefix_dir) - prefix_len);
- unlink_file(prefix_dir);
- if (i == list->count)
- break;
- }
- closedir(dir);
- filelist_free(list);
-}
-
-
-/*
-** Check a path to see if it's okay (not likely to confuse us). This
-** ensures that it doesn't contain elements like "./" or "../" and doesn't
-** contain doubled slashes.
-*/
-static bool
-bad_path(const char *p)
-{
- if (strlen(p) >= MAX_DIR_LEN)
- return true;
- while (*p) {
- if (p[0] == '.' && (p[1] == '/' || (p[1] == '.' && p[2] == '/')))
- return true;
- while (*p && *p != '/')
- p++;
- if (p[0] == '/' && p[1] == '/')
- return true;
- if (*p == '/')
- p++;
- }
- return false;
-}
-
-
-/*
-** Main routine. Parse options, initialize the storage manager, and
-** initalize various global variables, and then go into a loop calling
-** process_line and unlink_filelist as needed.
-*/
-int
-main(int argc, char *argv[])
-{
- const char *name;
- char *p, **arg;
- QIOSTATE *qp;
- filelist *list;
- int filecount, deleted;
- bool empty_error = false;
-
- /* Establish our identity. Since we use the storage manager, we need to
- set up syslog as well, although we won't use it ourselves. */
- name = argv[0];
- if (*name == '\0')
- name = "fastrm";
- else {
- p = strrchr(name, '/');
- if (p != NULL)
- name = p + 1;
- }
- message_program_name = name;
- openlog(name, LOG_CONS | LOG_PID, LOG_INN_PROG);
-
- /* If we're running as root, unlink may remove directories. */
- unlink_dangerous = (geteuid() == 0);
-
- /* Unfortunately, we can't use getopt, because several of our options
- take optional arguments. Bleh. */
- arg = argv + 1;
- while (argc >= 2 && **arg == '-') {
- p = *arg;
- while (*++p) {
- switch (*p) {
- default:
- die("invalid option -- %c", *p);
- case 'a':
- case 'r':
- continue;
- case 'c':
- chdir_threshold = 1;
- if (!CTYPE(isdigit, p[1]))
- continue;
- chdir_threshold = atoi(p + 1);
- break;
- case 'd':
- debug_only = true;
- continue;
- case 'e':
- empty_error = true;
- continue;
- case 's':
- sort_threshold = 5;
- if (!CTYPE(isdigit, p[1]))
- continue;
- sort_threshold = atoi(p + 1);
- break;
- case 'u':
- relative_threshold = 1;
- if (!CTYPE(isdigit, p[1]))
- continue;
- relative_threshold = atoi(p + 1);
- if (relative_threshold >= (int) strlen(dotdots) / 3)
- relative_threshold = strlen(dotdots) / 3 - 1;
- break;
- }
- break;
- }
- argc--;
- arg++;
- }
- if (argc != 2)
- die("usage error, wrong number of arguments");
-
- /* The remaining argument is the base path. Make sure it's valid and
- not excessively large and then change to it. */
- base_dir = *arg;
- if (*base_dir != '/' || bad_path(base_dir))
- die("bad base path %s", base_dir);
- strlcpy(current_dir, base_dir, sizeof(current_dir));
- if (chdir(current_dir) < 0)
- sysdie("can't chdir to base path %s", current_dir);
-
- /* Open our input stream and then loop through it, building filelists
- and processing them until done. */
- qp = QIOfdopen(fileno(stdin));
- if (qp == NULL)
- sysdie("can't reopen stdin");
- while ((list = process_line(qp, &filecount, &deleted)) != NULL) {
- empty_error = false;
- unlink_filelist(list, filecount);
- }
- if (deleted > 0)
- empty_error = false;
-
- /* All done. */
- SMshutdown();
- if (empty_error)
- die("no files to remove");
- exit(error_count > 0 ? 1 : 0);
-}
~ian / inn-innduct.git / blobdiff