chiark / gitweb /
libudev: switch API from devpath to syspath
[elogind.git] / udev / lib / libudev-util.c
index dfd5f3c3fb0af26d1f6c5cc046e1eb3ecf1365a5..7053a2f82554726508bd39110f526233b7a1259d 100644 (file)
 #include <errno.h>
 #include <string.h>
 #include <dirent.h>
+#include <ctype.h>
+#include <fcntl.h>
 #include <sys/stat.h>
 
 #include "libudev.h"
 #include "libudev-private.h"
-#include "../udev.h"
 
-static ssize_t get_sys_link(struct udev *udev, const char *slink, const char *devpath, char *subsystem, size_t size)
+static ssize_t get_sys_link(struct udev *udev, const char *slink, const char *syspath, char *subsystem, size_t size)
 {
-       char path[PATH_SIZE];
+       char path[UTIL_PATH_SIZE];
        ssize_t len;
        const char *pos;
 
-       strlcpy(path, udev_get_sys_path(udev), sizeof(path));
-       strlcat(path, devpath, sizeof(path));
-       strlcat(path, "/", sizeof(path));
-       strlcat(path, slink, sizeof(path));
+       util_strlcpy(path, syspath, sizeof(path));
+       util_strlcat(path, "/", sizeof(path));
+       util_strlcat(path, slink, sizeof(path));
        len = readlink(path, path, sizeof(path));
        if (len < 0 || len >= (ssize_t) sizeof(path))
                return -1;
@@ -50,59 +50,51 @@ static ssize_t get_sys_link(struct udev *udev, const char *slink, const char *de
        if (pos == NULL)
                return -1;
        pos = &pos[1];
-       return strlcpy(subsystem, pos, size);
+       return util_strlcpy(subsystem, pos, size);
 }
 
-ssize_t util_get_sys_subsystem(struct udev *udev, const char *devpath, char *subsystem, size_t size)
+ssize_t util_get_sys_subsystem(struct udev *udev, const char *syspath, char *subsystem, size_t size)
 {
-       return get_sys_link(udev, "subsystem", devpath, subsystem, size);
+       return get_sys_link(udev, "subsystem", syspath, subsystem, size);
 }
 
-ssize_t util_get_sys_driver(struct udev *udev, const char *devpath, char *driver, size_t size)
+ssize_t util_get_sys_driver(struct udev *udev, const char *syspath, char *driver, size_t size)
 {
-       return get_sys_link(udev, "driver", devpath, driver, size);
+       return get_sys_link(udev, "driver", syspath, driver, size);
 }
 
-int util_resolve_sys_link(struct udev *udev, char *devpath, size_t size)
+int util_resolve_sys_link(struct udev *udev, char *syspath, size_t size)
 {
-       char link_path[PATH_SIZE];
-       char link_target[PATH_SIZE];
+       char link_target[UTIL_PATH_SIZE];
+
        int len;
        int i;
        int back;
 
-       strlcpy(link_path, udev_get_sys_path(udev), sizeof(link_path));
-       strlcat(link_path, devpath, sizeof(link_path));
-       len = readlink(link_path, link_target, sizeof(link_target));
+       len = readlink(syspath, link_target, sizeof(link_target));
        if (len <= 0)
                return -1;
        link_target[len] = '\0';
-       dbg(udev, "path link '%s' points to '%s'\n", devpath, link_target);
+       dbg(udev, "path link '%s' points to '%s'\n", syspath, link_target);
 
        for (back = 0; strncmp(&link_target[back * 3], "../", 3) == 0; back++)
                ;
-       dbg(udev, "base '%s', tail '%s', back %i\n", devpath, &link_target[back * 3], back);
+       dbg(udev, "base '%s', tail '%s', back %i\n", syspath, &link_target[back * 3], back);
        for (i = 0; i <= back; i++) {
-               char *pos = strrchr(devpath, '/');
+               char *pos = strrchr(syspath, '/');
 
                if (pos == NULL)
                        return -1;
                pos[0] = '\0';
        }
-       dbg(udev, "after moving back '%s'\n", devpath);
-       strlcat(devpath, "/", size);
-       strlcat(devpath, &link_target[back * 3], size);
+       dbg(udev, "after moving back '%s'\n", syspath);
+       util_strlcat(syspath, "/", size);
+       util_strlcat(syspath, &link_target[back * 3], size);
        return 0;
 }
 
-struct util_name_entry {
-       struct list_head node;
-       char *name;
-       int *i;
-};
-
 struct util_name_entry *util_name_list_add(struct udev *udev, struct list_head *name_list,
-                                          const char *name, int sort)
+                                          const char *name, const char *value, int sort)
 {
        struct util_name_entry *name_loop;
        struct util_name_entry *name_new;
@@ -122,10 +114,23 @@ struct util_name_entry *util_name_list_add(struct udev *udev, struct list_head *
                }
        }
 
+       name_new = malloc(sizeof(struct util_name_entry));
+       if (name_new == NULL)
+               return NULL;
+       memset(name_new, 0x00, sizeof(struct util_name_entry));
        name_new->name = strdup(name);
-       if (name_new->name == NULL)
+       if (name_new->name == NULL) {
+               free(name_new);
                return NULL;
-       dbg(udev, "adding '%s'\n", name_new->name);
+       }
+       if (value != NULL) {
+               name_new->value = strdup(value);
+               if (name_new->value == NULL) {
+                       free(name_new);
+                       return NULL;
+               }
+       }
+       dbg(udev, "adding '%s=%s'\n", name_new->name, name_new->value);
        list_add_tail(&name_new->node, &name_loop->node);
        return name_new;
 }
@@ -138,6 +143,7 @@ void util_name_list_cleanup(struct udev *udev, struct list_head *name_list)
        list_for_each_entry_safe(name_loop, name_tmp, name_list, node) {
                list_del(&name_loop->node);
                free(name_loop->name);
+               free(name_loop->value);
                free(name_loop);
        }
 }
@@ -212,3 +218,222 @@ void util_remove_trailing_chars(char *path, char c)
        while (len > 0 && path[len-1] == c)
                path[--len] = '\0';
 }
+
+size_t util_strlcpy(char *dst, const char *src, size_t size)
+{
+       size_t bytes = 0;
+       char *q = dst;
+       const char *p = src;
+       char ch;
+
+       while ((ch = *p++)) {
+               if (bytes+1 < size)
+                       *q++ = ch;
+               bytes++;
+       }
+
+       /* If size == 0 there is no space for a final null... */
+       if (size)
+               *q = '\0';
+       return bytes;
+}
+
+size_t util_strlcat(char *dst, const char *src, size_t size)
+{
+       size_t bytes = 0;
+       char *q = dst;
+       const char *p = src;
+       char ch;
+
+       while (bytes < size && *q) {
+               q++;
+               bytes++;
+       }
+       if (bytes == size)
+               return (bytes + strlen(src));
+
+       while ((ch = *p++)) {
+               if (bytes+1 < size)
+               *q++ = ch;
+               bytes++;
+       }
+
+       *q = '\0';
+       return bytes;
+}
+
+/* count of characters used to encode one unicode char */
+static int utf8_encoded_expected_len(const char *str)
+{
+       unsigned char c = (unsigned char)str[0];
+
+       if (c < 0x80)
+               return 1;
+       if ((c & 0xe0) == 0xc0)
+               return 2;
+       if ((c & 0xf0) == 0xe0)
+               return 3;
+       if ((c & 0xf8) == 0xf0)
+               return 4;
+       if ((c & 0xfc) == 0xf8)
+               return 5;
+       if ((c & 0xfe) == 0xfc)
+               return 6;
+       return 0;
+}
+
+/* decode one unicode char */
+static int utf8_encoded_to_unichar(const char *str)
+{
+       int unichar;
+       int len;
+       int i;
+
+       len = utf8_encoded_expected_len(str);
+       switch (len) {
+       case 1:
+               return (int)str[0];
+       case 2:
+               unichar = str[0] & 0x1f;
+               break;
+       case 3:
+               unichar = (int)str[0] & 0x0f;
+               break;
+       case 4:
+               unichar = (int)str[0] & 0x07;
+               break;
+       case 5:
+               unichar = (int)str[0] & 0x03;
+               break;
+       case 6:
+               unichar = (int)str[0] & 0x01;
+               break;
+       default:
+               return -1;
+       }
+
+       for (i = 1; i < len; i++) {
+               if (((int)str[i] & 0xc0) != 0x80)
+                       return -1;
+               unichar <<= 6;
+               unichar |= (int)str[i] & 0x3f;
+       }
+
+       return unichar;
+}
+
+/* expected size used to encode one unicode char */
+static int utf8_unichar_to_encoded_len(int unichar)
+{
+       if (unichar < 0x80)
+               return 1;
+       if (unichar < 0x800)
+               return 2;
+       if (unichar < 0x10000)
+               return 3;
+       if (unichar < 0x200000)
+               return 4;
+       if (unichar < 0x4000000)
+               return 5;
+       return 6;
+}
+
+/* check if unicode char has a valid numeric range */
+static int utf8_unichar_valid_range(int unichar)
+{
+       if (unichar > 0x10ffff)
+               return 0;
+       if ((unichar & 0xfffff800) == 0xd800)
+               return 0;
+       if ((unichar > 0xfdcf) && (unichar < 0xfdf0))
+               return 0;
+       if ((unichar & 0xffff) == 0xffff)
+               return 0;
+       return 1;
+}
+
+/* validate one encoded unicode char and return its length */
+static int utf8_encoded_valid_unichar(const char *str)
+{
+       int len;
+       int unichar;
+       int i;
+
+       len = utf8_encoded_expected_len(str);
+       if (len == 0)
+               return -1;
+
+       /* ascii is valid */
+       if (len == 1)
+               return 1;
+
+       /* check if expected encoded chars are available */
+       for (i = 0; i < len; i++)
+               if ((str[i] & 0x80) != 0x80)
+                       return -1;
+
+       unichar = utf8_encoded_to_unichar(str);
+
+       /* check if encoded length matches encoded value */
+       if (utf8_unichar_to_encoded_len(unichar) != len)
+               return -1;
+
+       /* check if value has valid range */
+       if (!utf8_unichar_valid_range(unichar))
+               return -1;
+
+       return len;
+}
+
+/* allow chars in whitelist, plain ascii, hex-escaping and valid utf8 */
+int util_replace_chars(char *str, const char *white)
+{
+       size_t i = 0;
+       int replaced = 0;
+
+       while (str[i] != '\0') {
+               int len;
+
+               /* accept whitelist */
+               if (white != NULL && strchr(white, str[i]) != NULL) {
+                       i++;
+                       continue;
+               }
+
+               /* accept plain ascii char */
+               if ((str[i] >= '0' && str[i] <= '9') ||
+                   (str[i] >= 'A' && str[i] <= 'Z') ||
+                   (str[i] >= 'a' && str[i] <= 'z')) {
+                       i++;
+                       continue;
+               }
+
+               /* accept hex encoding */
+               if (str[i] == '\\' && str[i+1] == 'x') {
+                       i += 2;
+                       continue;
+               }
+
+               /* accept valid utf8 */
+               len = utf8_encoded_valid_unichar(&str[i]);
+               if (len > 1) {
+                       i += len;
+                       continue;
+               }
+
+               /* if space is allowed, replace whitespace with ordinary space */
+               if (isspace(str[i]) && strchr(white, ' ') != NULL) {
+                       str[i] = ' ';
+                       i++;
+                       replaced++;
+                       continue;
+               }
+
+               /* everything else is replaced with '_' */
+               str[i] = '_';
+               i++;
+               replaced++;
+       }
+
+       return replaced;
+}