Adding upstream version 247.3.upstream/247.3upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 214 insertions, 0 deletions

diff --git a/src/libudev/libudev-util.c b/src/libudev/libudev-util.c
new file mode 100644
index 0000000..bbb2879
--- /dev/null
+++ b/src/libudev/libudev-util.c
@@ -0,0 +1,214 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <ctype.h>
+#include <errno.h>
+
+#include "sd-device.h"
+
+#include "device-nodes.h"
+#include "libudev-util.h"
+#include "string-util.h"
+#include "strxcpyx.h"
+#include "utf8.h"
+
+/**
+ * SECTION:libudev-util
+ * @short_description: utils
+ *
+ * Utilities useful when dealing with devices and device node names.
+ */
+
+/* handle "[<SUBSYSTEM>/<KERNEL>]<attribute>" format */
+int util_resolve_subsys_kernel(const char *string, char *result, size_t maxsize, bool read_value) {
+        char temp[UTIL_PATH_SIZE], *subsys, *sysname, *attr;
+        _cleanup_(sd_device_unrefp) sd_device *dev = NULL;
+        const char *val;
+        int r;
+
+        if (string[0] != '[')
+                return -EINVAL;
+
+        strscpy(temp, sizeof(temp), string);
+
+        subsys = &temp[1];
+
+        sysname = strchr(subsys, '/');
+        if (!sysname)
+                return -EINVAL;
+        sysname[0] = '\0';
+        sysname = &sysname[1];
+
+        attr = strchr(sysname, ']');
+        if (!attr)
+                return -EINVAL;
+        attr[0] = '\0';
+        attr = &attr[1];
+        if (attr[0] == '/')
+                attr = &attr[1];
+        if (attr[0] == '\0')
+                attr = NULL;
+
+        if (read_value && !attr)
+                return -EINVAL;
+
+        r = sd_device_new_from_subsystem_sysname(&dev, subsys, sysname);
+        if (r < 0)
+                return r;
+
+        if (read_value) {
+                r = sd_device_get_sysattr_value(dev, attr, &val);
+                if (r < 0 && r != -ENOENT)
+                        return r;
+                if (r == -ENOENT)
+                        result[0] = '\0';
+                else
+                        strscpy(result, maxsize, val);
+                log_debug("value '[%s/%s]%s' is '%s'", subsys, sysname, attr, result);
+        } else {
+                r = sd_device_get_syspath(dev, &val);
+                if (r < 0)
+                        return r;
+
+                strscpyl(result, maxsize, val, attr ? "/" : NULL, attr ?: NULL, NULL);
+                log_debug("path '[%s/%s]%s' is '%s'", subsys, sysname, strempty(attr), result);
+        }
+        return 0;
+}
+
+size_t util_path_encode(const char *src, char *dest, size_t size) {
+        size_t i, j;
+
+        assert(src);
+        assert(dest);
+
+        for (i = 0, j = 0; src[i] != '\0'; i++) {
+                if (src[i] == '/') {
+                        if (j+4 >= size) {
+                                j = 0;
+                                break;
+                        }
+                        memcpy(&dest[j], "\\x2f", 4);
+                        j += 4;
+                } else if (src[i] == '\\') {
+                        if (j+4 >= size) {
+                                j = 0;
+                                break;
+                        }
+                        memcpy(&dest[j], "\\x5c", 4);
+                        j += 4;
+                } else {
+                        if (j+1 >= size) {
+                                j = 0;
+                                break;
+                        }
+                        dest[j] = src[i];
+                        j++;
+                }
+        }
+        dest[j] = '\0';
+        return j;
+}
+
+/*
+ * Copy from 'str' to 'to', while removing all leading and trailing whitespace,
+ * and replacing each run of consecutive whitespace with a single underscore.
+ * The chars from 'str' are copied up to the \0 at the end of the string, or
+ * at most 'len' chars.  This appends \0 to 'to', at the end of the copied
+ * characters.
+ *
+ * If 'len' chars are copied into 'to', the final \0 is placed at len+1
+ * (i.e. 'to[len] = \0'), so the 'to' buffer must have at least len+1
+ * chars available.
+ *
+ * Note this may be called with 'str' == 'to', i.e. to replace whitespace
+ * in-place in a buffer.  This function can handle that situation.
+ *
+ * Note that only 'len' characters are read from 'str'.
+ */
+size_t util_replace_whitespace(const char *str, char *to, size_t len) {
+        bool is_space = false;
+        size_t i, j;
+
+        assert(str);
+        assert(to);
+
+        i = strspn(str, WHITESPACE);
+
+        for (j = 0; j < len && i < len && str[i] != '\0'; i++) {
+                if (isspace(str[i])) {
+                        is_space = true;
+                        continue;
+                }
+
+                if (is_space) {
+                        if (j + 1 >= len)
+                                break;
+
+                        to[j++] = '_';
+                        is_space = false;
+                }
+                to[j++] = str[i];
+        }
+
+        to[j] = '\0';
+        return j;
+}
+
+/* allow chars in allow list, plain ascii, hex-escaping and valid utf8 */
+size_t util_replace_chars(char *str, const char *allow) {
+        size_t i = 0, replaced = 0;
+
+        assert(str);
+
+        while (str[i] != '\0') {
+                int len;
+
+                if (allow_listed_char_for_devnode(str[i], allow)) {
+                        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, (size_t) -1);
+                if (len > 1) {
+                        i += len;
+                        continue;
+                }
+
+                /* if space is allowed, replace whitespace with ordinary space */
+                if (isspace(str[i]) && allow && strchr(allow, ' ')) {
+                        str[i] = ' ';
+                        i++;
+                        replaced++;
+                        continue;
+                }
+
+                /* everything else is replaced with '_' */
+                str[i] = '_';
+                i++;
+                replaced++;
+        }
+        return replaced;
+}
+
+/**
+ * udev_util_encode_string:
+ * @str: input string to be encoded
+ * @str_enc: output string to store the encoded input string
+ * @len: maximum size of the output string, which may be
+ *       four times as long as the input string
+ *
+ * Encode all potentially unsafe characters of a string to the
+ * corresponding 2 char hex value prefixed by '\x'.
+ *
+ * Returns: 0 if the entire string was copied, non-zero otherwise.
+ **/
+_public_ int udev_util_encode_string(const char *str, char *str_enc, size_t len) {
+        return encode_devnode_name(str, str_enc, len);
+}