From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Sat, 18 Jan 2025 01:39:21 +0000 (+0900)
Subject: sd-device: use sd_device_get_sysattr_value() to read uevent file
X-Git-Tag: v258-rc1~1510^2~2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=17dc9ec4b6e82fc2a4f9809011e154f538eb8b9c;p=thirdparty%2Fsystemd.git

sd-device: use sd_device_get_sysattr_value() to read uevent file

This also replaces the custom parser with strv_split_newlines_full().
No functional change, just refactoring.
---

diff --git a/src/libsystemd/sd-device/sd-device.c b/src/libsystemd/sd-device/sd-device.c
index c6d293793ce..b74ea6a1c1a 100644
--- a/src/libsystemd/sd-device/sd-device.c
+++ b/src/libsystemd/sd-device/sd-device.c
@@ -787,89 +787,52 @@ static int handle_uevent_line(
 }
 
 int device_read_uevent_file(sd_device *device) {
-        _cleanup_free_ char *uevent = NULL;
-        const char *syspath, *key = NULL, *value = NULL, *major = NULL, *minor = NULL;
-        char *path;
-        size_t uevent_len;
         int r;
 
-        enum {
-                PRE_KEY,
-                KEY,
-                PRE_VALUE,
-                VALUE,
-                INVALID_LINE,
-        } state = PRE_KEY;
-
         assert(device);
 
         if (device->uevent_loaded || device->sealed)
                 return 0;
 
-        r = sd_device_get_syspath(device, &syspath);
-        if (r < 0)
-                return r;
-
         device->uevent_loaded = true;
 
-        path = strjoina(syspath, "/uevent");
-
-        r = read_full_virtual_file(path, &uevent, &uevent_len);
-        if (r == -EACCES || ERRNO_IS_NEG_DEVICE_ABSENT(r))
+        const char *uevent;
+        r = sd_device_get_sysattr_value(device, "uevent", &uevent);
+        if (ERRNO_IS_NEG_PRIVILEGE(r) || ERRNO_IS_NEG_DEVICE_ABSENT(r))
                 /* The uevent files may be write-only, the device may be already removed, or the device
                  * may not have the uevent file. */
                 return 0;
         if (r < 0)
-                return log_device_debug_errno(device, r, "sd-device: Failed to read uevent file '%s': %m", path);
-
-        for (size_t i = 0; i < uevent_len; i++)
-                switch (state) {
-                case PRE_KEY:
-                        if (!strchr(NEWLINE, uevent[i])) {
-                                key = &uevent[i];
-
-                                state = KEY;
-                        }
-
-                        break;
-                case KEY:
-                        if (uevent[i] == '=') {
-                                uevent[i] = '\0';
+                return log_device_debug_errno(device, r, "sd-device: Failed to read uevent file: %m");
 
-                                state = PRE_VALUE;
-                        } else if (strchr(NEWLINE, uevent[i])) {
-                                uevent[i] = '\0';
-                                log_device_debug(device, "sd-device: Invalid uevent line '%s', ignoring", key);
-
-                                state = PRE_KEY;
-                        }
-
-                        break;
-                case PRE_VALUE:
-                        value = &uevent[i];
-                        state = VALUE;
-
-                        _fallthrough_; /* to handle empty property */
-                case VALUE:
-                        if (strchr(NEWLINE, uevent[i])) {
-                                uevent[i] = '\0';
+        _cleanup_strv_free_ char **v = NULL;
+        r = strv_split_newlines_full(&v, uevent, EXTRACT_RETAIN_ESCAPE);
+        if (r < 0)
+                return log_device_debug_errno(device, r, "sd-device: Failed to parse uevent file: %m");
 
-                                r = handle_uevent_line(device, key, value, &major, &minor);
-                                if (r < 0)
-                                        log_device_debug_errno(device, r, "sd-device: Failed to handle uevent entry '%s=%s', ignoring: %m", key, value);
+        const char *major = NULL, *minor = NULL;
+        STRV_FOREACH(s, v) {
+                char *eq = strchr(*s, '=');
+                if (!eq) {
+                        log_device_debug(device, "sd-device: Invalid uevent line, ignoring: %s", *s);
+                        continue;
+                }
 
-                                state = PRE_KEY;
-                        }
+                *eq = '\0';
 
-                        break;
-                default:
-                        assert_not_reached();
-                }
+                r = handle_uevent_line(device, *s, eq + 1, &major, &minor);
+                if (r < 0)
+                        log_device_debug_errno(device, r,
+                                               "sd-device: Failed to handle uevent entry '%s=%s', ignoring: %m",
+                                               *s, eq + 1);
+        }
 
         if (major) {
                 r = device_set_devnum(device, major, minor);
                 if (r < 0)
-                        log_device_debug_errno(device, r, "sd-device: Failed to set 'MAJOR=%s' or 'MINOR=%s' from '%s', ignoring: %m", major, strna(minor), path);
+                        log_device_debug_errno(device, r,
+                                               "sd-device: Failed to set 'MAJOR=%s' and/or 'MINOR=%s' from uevent, ignoring: %m",
+                                               major, strna(minor));
         }
 
         return 0;