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authorMichael Tokarev <mjt@tls.msk.ru>2014-12-20 08:48:44 +0000
committerMichael Tokarev <mjt@tls.msk.ru>2014-12-20 08:48:44 +0000
commit489bea7ee8e1dbecfa517b8415568044ab57c73a (patch)
tree44d4878d4c7da3f4908ea9a765ef9b8f9c141756 /lib.c
mdadm (3.3.2-5) unstable; urgency=medium
* use-tempnode-not-devnode.patch: change udev rules file to use $tempnode which works both on wheezy and jessie udev, instead of $devnode which only works in jessie. At this stage it is better to make rules file compatible with old version instead of adding versioned dependency. Should be removed for jessie+1. (Closes: #770883) * fix Closes: list in previous entry (Closes: #771852) # imported from the archive
Diffstat (limited to 'lib.c')
-rw-r--r--lib.c475
1 files changed, 475 insertions, 0 deletions
diff --git a/lib.c b/lib.c
new file mode 100644
index 0000000..6808f62
--- /dev/null
+++ b/lib.c
@@ -0,0 +1,475 @@
+/*
+ * mdadm - manage Linux "md" devices aka RAID arrays.
+ *
+ * Copyright (C) 2011 Neil Brown <neilb@suse.de>
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Neil Brown
+ * Email: <neilb@suse.de>
+ */
+
+#include "mdadm.h"
+#include "dlink.h"
+#include <ctype.h>
+
+/* This fill contains various 'library' style function. They
+ * have no dependency on anything outside this file.
+ */
+
+int get_mdp_major(void)
+{
+static int mdp_major = -1;
+ FILE *fl;
+ char *w;
+ int have_block = 0;
+ int have_devices = 0;
+ int last_num = -1;
+
+ if (mdp_major != -1)
+ return mdp_major;
+ fl = fopen("/proc/devices", "r");
+ if (!fl)
+ return -1;
+ while ((w = conf_word(fl, 1))) {
+ if (have_block && strcmp(w, "devices:")==0)
+ have_devices = 1;
+ have_block = (strcmp(w, "Block")==0);
+ if (isdigit(w[0]))
+ last_num = atoi(w);
+ if (have_devices && strcmp(w, "mdp")==0)
+ mdp_major = last_num;
+ free(w);
+ }
+ fclose(fl);
+ return mdp_major;
+}
+
+char *devid2kname(int devid)
+{
+ char path[30];
+ char link[200];
+ static char devnm[32];
+ char *cp;
+ int n;
+
+ /* Look at the
+ * /sys/dev/block/%d:%d link which must look like
+ * and take the last component.
+ */
+ sprintf(path, "/sys/dev/block/%d:%d", major(devid),
+ minor(devid));
+ n = readlink(path, link, sizeof(link)-1);
+ if (n > 0) {
+ link[n] = 0;
+ cp = strrchr(link, '/');
+ if (cp) {
+ strcpy(devnm, cp+1);
+ return devnm;
+ }
+ }
+ return NULL;
+}
+
+char *devid2devnm(int devid)
+{
+ char path[30];
+ char link[200];
+ static char devnm[32];
+ char *cp, *ep;
+ int n;
+
+ /* Might be an extended-minor partition or a
+ * named md device. Look at the
+ * /sys/dev/block/%d:%d link which must look like
+ * ../../block/mdXXX/mdXXXpYY
+ * or
+ * ...../block/md_FOO
+ */
+ sprintf(path, "/sys/dev/block/%d:%d", major(devid),
+ minor(devid));
+ n = readlink(path, link, sizeof(link)-1);
+ if (n > 0) {
+ link[n] = 0;
+ cp = strstr(link, "/block/");
+ if (cp) {
+ cp += 7;
+ ep = strchr(cp, '/');
+ if (ep)
+ *ep = 0;
+ strcpy(devnm, cp);
+ return devnm;
+ }
+ }
+ if (major(devid) == MD_MAJOR)
+ sprintf(devnm,"md%d", minor(devid));
+ else if (major(devid) == (unsigned)get_mdp_major())
+ sprintf(devnm,"md_d%d",
+ (minor(devid)>>MdpMinorShift));
+ else
+ return NULL;
+ return devnm;
+}
+
+char *stat2devnm(struct stat *st)
+{
+ if ((S_IFMT & st->st_mode) != S_IFBLK)
+ return NULL;
+ return devid2devnm(st->st_rdev);
+}
+
+char *fd2devnm(int fd)
+{
+ struct stat stb;
+ if (fstat(fd, &stb) == 0)
+ return stat2devnm(&stb);
+ return NULL;
+}
+
+/*
+ * convert a major/minor pair for a block device into a name in /dev, if possible.
+ * On the first call, walk /dev collecting name.
+ * Put them in a simple linked listfor now.
+ */
+struct devmap {
+ int major, minor;
+ char *name;
+ struct devmap *next;
+} *devlist = NULL;
+int devlist_ready = 0;
+
+int add_dev(const char *name, const struct stat *stb, int flag, struct FTW *s)
+{
+ struct stat st;
+
+ if (S_ISLNK(stb->st_mode)) {
+ if (stat(name, &st) != 0)
+ return 0;
+ stb = &st;
+ }
+
+ if ((stb->st_mode&S_IFMT)== S_IFBLK) {
+ char *n = xstrdup(name);
+ struct devmap *dm = xmalloc(sizeof(*dm));
+ if (strncmp(n, "/dev/./", 7)==0)
+ strcpy(n+4, name+6);
+ if (dm) {
+ dm->major = major(stb->st_rdev);
+ dm->minor = minor(stb->st_rdev);
+ dm->name = n;
+ dm->next = devlist;
+ devlist = dm;
+ }
+ }
+ return 0;
+}
+
+#ifndef HAVE_NFTW
+#ifdef HAVE_FTW
+int add_dev_1(const char *name, const struct stat *stb, int flag)
+{
+ return add_dev(name, stb, flag, NULL);
+}
+int nftw(const char *path, int (*han)(const char *name, const struct stat *stb, int flag, struct FTW *s), int nopenfd, int flags)
+{
+ return ftw(path, add_dev_1, nopenfd);
+}
+#else
+int nftw(const char *path, int (*han)(const char *name, const struct stat *stb, int flag, struct FTW *s), int nopenfd, int flags)
+{
+ return 0;
+}
+#endif /* HAVE_FTW */
+#endif /* HAVE_NFTW */
+
+/*
+ * Find a block device with the right major/minor number.
+ * If we find multiple names, choose the shortest.
+ * If we find a name in /dev/md/, we prefer that.
+ * This applies only to names for MD devices.
+ * If 'prefer' is set (normally to e.g. /by-path/)
+ * then we prefer a name which contains that string.
+ */
+char *map_dev_preferred(int major, int minor, int create,
+ char *prefer)
+{
+ struct devmap *p;
+ char *regular = NULL, *preferred=NULL;
+ int did_check = 0;
+
+ if (major == 0 && minor == 0)
+ return NULL;
+
+ retry:
+ if (!devlist_ready) {
+ char *dev = "/dev";
+ struct stat stb;
+ while(devlist) {
+ struct devmap *d = devlist;
+ devlist = d->next;
+ free(d->name);
+ free(d);
+ }
+ if (lstat(dev, &stb)==0 &&
+ S_ISLNK(stb.st_mode))
+ dev = "/dev/.";
+ nftw(dev, add_dev, 10, FTW_PHYS);
+ devlist_ready=1;
+ did_check = 1;
+ }
+
+ for (p=devlist; p; p=p->next)
+ if (p->major == major &&
+ p->minor == minor) {
+ if (strncmp(p->name, "/dev/md/",8) == 0
+ || (prefer && strstr(p->name, prefer))) {
+ if (preferred == NULL ||
+ strlen(p->name) < strlen(preferred))
+ preferred = p->name;
+ } else {
+ if (regular == NULL ||
+ strlen(p->name) < strlen(regular))
+ regular = p->name;
+ }
+ }
+ if (!regular && !preferred && !did_check) {
+ devlist_ready = 0;
+ goto retry;
+ }
+ if (create && !regular && !preferred) {
+ static char buf[30];
+ snprintf(buf, sizeof(buf), "%d:%d", major, minor);
+ regular = buf;
+ }
+
+ return preferred ? preferred : regular;
+}
+
+/* conf_word gets one word from the conf file.
+ * if "allow_key", then accept words at the start of a line,
+ * otherwise stop when such a word is found.
+ * We assume that the file pointer is at the end of a word, so the
+ * next character is a space, or a newline. If not, it is the start of a line.
+ */
+
+char *conf_word(FILE *file, int allow_key)
+{
+ int wsize = 100;
+ int len = 0;
+ int c;
+ int quote;
+ int wordfound = 0;
+ char *word = xmalloc(wsize);
+
+ while (wordfound==0) {
+ /* at the end of a word.. */
+ c = getc(file);
+ if (c == '#')
+ while (c != EOF && c != '\n')
+ c = getc(file);
+ if (c == EOF) break;
+ if (c == '\n') continue;
+
+ if (c != ' ' && c != '\t' && ! allow_key) {
+ ungetc(c, file);
+ break;
+ }
+ /* looks like it is safe to get a word here, if there is one */
+ quote = 0;
+ /* first, skip any spaces */
+ while (c == ' ' || c == '\t')
+ c = getc(file);
+ if (c != EOF && c != '\n' && c != '#') {
+ /* we really have a character of a word, so start saving it */
+ while (c != EOF && c != '\n' && (quote || (c!=' ' && c != '\t'))) {
+ wordfound = 1;
+ if (quote && c == quote) quote = 0;
+ else if (quote == 0 && (c == '\'' || c == '"'))
+ quote = c;
+ else {
+ if (len == wsize-1) {
+ wsize += 100;
+ word = xrealloc(word, wsize);
+ }
+ word[len++] = c;
+ }
+ c = getc(file);
+ /* Hack for broken kernels (2.6.14-.24) that put
+ * "active(auto-read-only)"
+ * in /proc/mdstat instead of
+ * "active (auto-read-only)"
+ */
+ if (c == '(' && len >= 6
+ && strncmp(word+len-6, "active", 6) == 0)
+ c = ' ';
+ }
+ }
+ if (c != EOF) ungetc(c, file);
+ }
+ word[len] = 0;
+
+ /* Further HACK for broken kernels.. 2.6.14-2.6.24 */
+ if (strcmp(word, "auto-read-only)") == 0)
+ strcpy(word, "(auto-read-only)");
+
+/* printf("word is <%s>\n", word); */
+ if (!wordfound) {
+ free(word);
+ word = NULL;
+ }
+ return word;
+}
+
+void print_quoted(char *str)
+{
+ /* Printf the string with surrounding quotes
+ * iff needed.
+ * If no space, tab, or quote - leave unchanged.
+ * Else print surrounded by " or ', swapping quotes
+ * when we find one that will cause confusion.
+ */
+
+ char first_quote = 0, q;
+ char *c;
+
+ for (c = str; *c; c++) {
+ switch(*c) {
+ case '\'':
+ case '"':
+ first_quote = *c;
+ break;
+ case ' ':
+ case '\t':
+ first_quote = *c;
+ continue;
+ default:
+ continue;
+ }
+ break;
+ }
+ if (!first_quote) {
+ printf("%s", str);
+ return;
+ }
+
+ if (first_quote == '"')
+ q = '\'';
+ else
+ q = '"';
+ putchar(q);
+ for (c = str; *c; c++) {
+ if (*c == q) {
+ putchar(q);
+ q ^= '"' ^ '\'';
+ putchar(q);
+ }
+ putchar(*c);
+ }
+ putchar(q);
+}
+
+void print_escape(char *str)
+{
+ /* print str, but change space and tab to '_'
+ * as is suitable for device names
+ */
+ for (; *str ; str++) {
+ switch (*str) {
+ case ' ':
+ case '\t':
+ putchar('_');
+ break;
+ case '/':
+ putchar('-');
+ break;
+ default:
+ putchar(*str);
+ }
+ }
+}
+
+int check_env(char *name)
+{
+ char *val = getenv(name);
+
+ if (val && atoi(val) == 1)
+ return 1;
+
+ return 0;
+}
+
+int use_udev(void)
+{
+ static int use = -1;
+ struct stat stb;
+
+ if (use < 0) {
+ use = ((stat("/dev/.udev", &stb) == 0
+ || stat("/run/udev", &stb) == 0)
+ && check_env("MDADM_NO_UDEV") == 0);
+ }
+ return use;
+}
+
+unsigned long GCD(unsigned long a, unsigned long b)
+{
+ while (a != b) {
+ if (a < b)
+ b -= a;
+ if (b < a)
+ a -= b;
+ }
+ return a;
+}
+
+/*
+ * conf_line reads one logical line from the conffile or mdstat.
+ * It skips comments and continues until it finds a line that starts
+ * with a non blank/comment. This character is pushed back for the next call
+ * A doubly linked list of words is returned.
+ * the first word will be a keyword. Other words will have had quotes removed.
+ */
+
+char *conf_line(FILE *file)
+{
+ char *w;
+ char *list;
+
+ w = conf_word(file, 1);
+ if (w == NULL) return NULL;
+
+ list = dl_strdup(w);
+ free(w);
+ dl_init(list);
+
+ while ((w = conf_word(file,0))){
+ char *w2 = dl_strdup(w);
+ free(w);
+ dl_add(list, w2);
+ }
+/* printf("got a line\n");*/
+ return list;
+}
+
+void free_line(char *line)
+{
+ char *w;
+ for (w=dl_next(line); w != line; w=dl_next(line)) {
+ dl_del(w);
+ dl_free(w);
+ }
+ dl_free(line);
+}