move common stuff from udev/ to private parts of libudev/

1 files changed, 446 insertions, 0 deletions

diff --git a/libudev/libudev-util-private.c b/libudev/libudev-util-private.c
new file mode 100644
index 0000000000..f22c04184b
--- /dev/null
+++ b/libudev/libudev-util-private.c
@@ -0,0 +1,446 @@
+/*
+ * libudev - interface to udev device information
+ *
+ * Copyright (C) 2004-2009 Kay Sievers <kay.sievers@vrfy.org>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <stddef.h>
+#include <unistd.h>
+#include <string.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <ctype.h>
+#include <pwd.h>
+#include <grp.h>
+#include <sys/wait.h>
+
+#include "libudev.h"
+#include "libudev-private.h"
+
+int util_create_path(struct udev *udev, const char *path)
+{
+	char p[UTIL_PATH_SIZE];
+	char *pos;
+	struct stat stats;
+	int ret;
+
+	util_strscpy(p, sizeof(p), path);
+	pos = strrchr(p, '/');
+	if (pos == p || pos == NULL)
+		return 0;
+
+	while (pos[-1] == '/')
+		pos--;
+	pos[0] = '\0';
+
+	dbg(udev, "stat '%s'\n", p);
+	if (stat(p, &stats) == 0 && (stats.st_mode & S_IFMT) == S_IFDIR)
+		return 0;
+
+	if (util_create_path(udev, p) != 0)
+		return -1;
+
+	dbg(udev, "mkdir '%s'\n", p);
+	udev_selinux_setfscreatecon(udev, p, S_IFDIR|0755);
+	ret = mkdir(p, 0755);
+	udev_selinux_resetfscreatecon(udev);
+	if (ret == 0)
+		return 0;
+
+	if (errno == EEXIST)
+		if (stat(p, &stats) == 0 && (stats.st_mode & S_IFMT) == S_IFDIR)
+			return 0;
+	return -1;
+}
+
+int util_delete_path(struct udev *udev, const char *path)
+{
+	char p[UTIL_PATH_SIZE];
+	char *pos;
+	int retval;
+
+	strcpy (p, path);
+	pos = strrchr(p, '/');
+	if (pos == p || pos == NULL)
+		return 0;
+
+	while (1) {
+		*pos = '\0';
+		pos = strrchr(p, '/');
+
+		/* don't remove the last one */
+		if ((pos == p) || (pos == NULL))
+			break;
+
+		/* remove if empty */
+		retval = rmdir(p);
+		if (errno == ENOENT)
+			retval = 0;
+		if (retval) {
+			if (errno == ENOTEMPTY)
+				return 0;
+			err(udev, "rmdir(%s) failed: %m\n", p);
+			break;
+		}
+		dbg(udev, "removed '%s'\n", p);
+	}
+	return 0;
+}
+
+/* Reset permissions on the device node, before unlinking it to make sure,
+ * that permisions of possible hard links will be removed too.
+ */
+int util_unlink_secure(struct udev *udev, const char *filename)
+{
+	int retval;
+
+	retval = chown(filename, 0, 0);
+	if (retval)
+		err(udev, "chown(%s, 0, 0) failed: %m\n", filename);
+
+	retval = chmod(filename, 0000);
+	if (retval)
+		err(udev, "chmod(%s, 0000) failed: %m\n", filename);
+
+	retval = unlink(filename);
+	if (errno == ENOENT)
+		retval = 0;
+
+	if (retval)
+		err(udev, "unlink(%s) failed: %m\n", filename);
+
+	return retval;
+}
+
+uid_t util_lookup_user(struct udev *udev, const char *user)
+{
+	char *endptr;
+	int buflen = sysconf(_SC_GETPW_R_SIZE_MAX);
+	char buf[buflen];
+	struct passwd pwbuf;
+	struct passwd *pw;
+	uid_t uid;
+
+	if (strcmp(user, "root") == 0)
+		return 0;
+	uid = strtoul(user, &endptr, 10);
+	if (endptr[0] == '\0')
+		return uid;
+
+	errno = 0;
+	getpwnam_r(user, &pwbuf, buf, buflen, &pw);
+	if (pw != NULL)
+		return pw->pw_uid;
+	if (errno == 0 || errno == ENOENT || errno == ESRCH)
+		err(udev, "specified user '%s' unknown\n", user);
+	else
+		err(udev, "error resolving user '%s': %m\n", user);
+	return 0;
+}
+
+gid_t util_lookup_group(struct udev *udev, const char *group)
+{
+	char *endptr;
+	int buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
+	char buf[buflen];
+	struct group grbuf;
+	struct group *gr;
+	gid_t gid = 0;
+
+	if (strcmp(group, "root") == 0)
+		return 0;
+	gid = strtoul(group, &endptr, 10);
+	if (endptr[0] == '\0')
+		return gid;
+
+	errno = 0;
+	getgrnam_r(group, &grbuf, buf, buflen, &gr);
+	if (gr != NULL)
+		return gr->gr_gid;
+	if (errno == 0 || errno == ENOENT || errno == ESRCH)
+		err(udev, "specified group '%s' unknown\n", group);
+	else
+		err(udev, "error resolving group '%s': %m\n", group);
+	return 0;
+}
+
+/* handle "[<SUBSYSTEM>/<KERNEL>]<attribute>" format */
+int util_resolve_subsys_kernel(struct udev *udev, const char *string,
+			       char *result, size_t maxsize, int read_value)
+{
+	char temp[UTIL_PATH_SIZE];
+	char *subsys;
+	char *sysname;
+	struct udev_device *dev;
+	char *attr;
+
+	if (string[0] != '[')
+		return -1;
+
+	util_strscpy(temp, sizeof(temp), string);
+
+	subsys = &temp[1];
+
+	sysname = strchr(subsys, '/');
+	if (sysname == NULL)
+		return -1;
+	sysname[0] = '\0';
+	sysname = &sysname[1];
+
+	attr = strchr(sysname, ']');
+	if (attr == NULL)
+		return -1;
+	attr[0] = '\0';
+	attr = &attr[1];
+	if (attr[0] == '/')
+		attr = &attr[1];
+	if (attr[0] == '\0')
+		attr = NULL;
+
+	if (read_value && attr == NULL)
+		return -1;
+
+	dev = udev_device_new_from_subsystem_sysname(udev, subsys, sysname);
+	if (dev == NULL)
+		return -1;
+
+	if (read_value) {
+		const char *val;
+
+		val = udev_device_get_sysattr_value(dev, attr);
+		if (val != NULL)
+			util_strscpy(result, maxsize, val);
+		else
+			result[0] = '\0';
+		info(udev, "value '[%s/%s]%s' is '%s'\n", subsys, sysname, attr, result);
+	} else {
+		size_t l;
+		char *s;
+
+		s = result;
+		l = util_strpcpyl(&s, maxsize, udev_device_get_syspath(dev), NULL);
+		if (attr != NULL)
+			util_strpcpyl(&s, l, "/", attr, NULL);
+		info(udev, "path '[%s/%s]%s' is '%s'\n", subsys, sysname, attr, result);
+	}
+	udev_device_unref(dev);
+	return 0;
+}
+
+int util_run_program(struct udev *udev, const char *command, char **envp,
+		     char *result, size_t ressize, size_t *reslen)
+{
+	int status;
+	int outpipe[2] = {-1, -1};
+	int errpipe[2] = {-1, -1};
+	pid_t pid;
+	char arg[UTIL_PATH_SIZE];
+	char program[UTIL_PATH_SIZE];
+	char *argv[(sizeof(arg) / 2) + 1];
+	int devnull;
+	int i;
+	int err = 0;
+
+	/* build argv from command */
+	util_strscpy(arg, sizeof(arg), command);
+	i = 0;
+	if (strchr(arg, ' ') != NULL) {
+		char *pos = arg;
+
+		while (pos != NULL && pos[0] != '\0') {
+			if (pos[0] == '\'') {
+				/* do not separate quotes */
+				pos++;
+				argv[i] = strsep(&pos, "\'");
+				while (pos != NULL && pos[0] == ' ')
+					pos++;
+			} else {
+				argv[i] = strsep(&pos, " ");
+			}
+			dbg(udev, "arg[%i] '%s'\n", i, argv[i]);
+			i++;
+		}
+		argv[i] = NULL;
+	} else {
+		argv[0] = arg;
+		argv[1] = NULL;
+	}
+	info(udev, "'%s'\n", command);
+
+	/* prepare pipes from child to parent */
+	if (result != NULL || udev_get_log_priority(udev) >= LOG_INFO) {
+		if (pipe(outpipe) != 0) {
+			err(udev, "pipe failed: %m\n");
+			return -1;
+		}
+	}
+	if (udev_get_log_priority(udev) >= LOG_INFO) {
+		if (pipe(errpipe) != 0) {
+			err(udev, "pipe failed: %m\n");
+			return -1;
+		}
+	}
+
+	/* allow programs in /lib/udev/ to be called without the path */
+	if (argv[0][0] != '/') {
+		util_strscpyl(program, sizeof(program), UDEV_PREFIX "/lib/udev/", argv[0], NULL);
+		argv[0] = program;
+	}
+
+	pid = fork();
+	switch(pid) {
+	case 0:
+		/* child closes parent ends of pipes */
+		if (outpipe[READ_END] > 0)
+			close(outpipe[READ_END]);
+		if (errpipe[READ_END] > 0)
+			close(errpipe[READ_END]);
+
+		/* discard child output or connect to pipe */
+		devnull = open("/dev/null", O_RDWR);
+		if (devnull > 0) {
+			dup2(devnull, STDIN_FILENO);
+			if (outpipe[WRITE_END] < 0)
+				dup2(devnull, STDOUT_FILENO);
+			if (errpipe[WRITE_END] < 0)
+				dup2(devnull, STDERR_FILENO);
+			close(devnull);
+		} else
+			err(udev, "open /dev/null failed: %m\n");
+		if (outpipe[WRITE_END] > 0) {
+			dup2(outpipe[WRITE_END], STDOUT_FILENO);
+			close(outpipe[WRITE_END]);
+		}
+		if (errpipe[WRITE_END] > 0) {
+			dup2(errpipe[WRITE_END], STDERR_FILENO);
+			close(errpipe[WRITE_END]);
+		}
+		execve(argv[0], argv, envp);
+		if (errno == ENOENT || errno == ENOTDIR) {
+			/* may be on a filesytem which is not mounted right now */
+			info(udev, "program '%s' not found\n", argv[0]);
+		} else {
+			/* other problems */
+			err(udev, "exec of program '%s' failed\n", argv[0]);
+		}
+		_exit(1);
+	case -1:
+		err(udev, "fork of '%s' failed: %m\n", argv[0]);
+		return -1;
+	default:
+		/* read from child if requested */
+		if (outpipe[READ_END] > 0 || errpipe[READ_END] > 0) {
+			ssize_t count;
+			size_t respos = 0;
+
+			/* parent closes child ends of pipes */
+			if (outpipe[WRITE_END] > 0)
+				close(outpipe[WRITE_END]);
+			if (errpipe[WRITE_END] > 0)
+				close(errpipe[WRITE_END]);
+
+			/* read child output */
+			while (outpipe[READ_END] > 0 || errpipe[READ_END] > 0) {
+				int fdcount;
+				fd_set readfds;
+
+				FD_ZERO(&readfds);
+				if (outpipe[READ_END] > 0)
+					FD_SET(outpipe[READ_END], &readfds);
+				if (errpipe[READ_END] > 0)
+					FD_SET(errpipe[READ_END], &readfds);
+				fdcount = select(UDEV_MAX(outpipe[READ_END], errpipe[READ_END])+1, &readfds, NULL, NULL, NULL);
+				if (fdcount < 0) {
+					if (errno == EINTR)
+						continue;
+					err = -1;
+					break;
+				}
+
+				/* get stdout */
+				if (outpipe[READ_END] > 0 && FD_ISSET(outpipe[READ_END], &readfds)) {
+					char inbuf[1024];
+					char *pos;
+					char *line;
+
+					count = read(outpipe[READ_END], inbuf, sizeof(inbuf)-1);
+					if (count <= 0) {
+						close(outpipe[READ_END]);
+						outpipe[READ_END] = -1;
+						if (count < 0) {
+							err(udev, "stdin read failed: %m\n");
+							err = -1;
+						}
+						continue;
+					}
+					inbuf[count] = '\0';
+
+					/* store result for rule processing */
+					if (result) {
+						if (respos + count < ressize) {
+							memcpy(&result[respos], inbuf, count);
+							respos += count;
+						} else {
+							err(udev, "ressize %ld too short\n", (long)ressize);
+							err = -1;
+						}
+					}
+					pos = inbuf;
+					while ((line = strsep(&pos, "\n")))
+						if (pos || line[0] != '\0')
+							info(udev, "'%s' (stdout) '%s'\n", argv[0], line);
+				}
+
+				/* get stderr */
+				if (errpipe[READ_END] > 0 && FD_ISSET(errpipe[READ_END], &readfds)) {
+					char errbuf[1024];
+					char *pos;
+					char *line;
+
+					count = read(errpipe[READ_END], errbuf, sizeof(errbuf)-1);
+					if (count <= 0) {
+						close(errpipe[READ_END]);
+						errpipe[READ_END] = -1;
+						if (count < 0)
+							err(udev, "stderr read failed: %m\n");
+						continue;
+					}
+					errbuf[count] = '\0';
+					pos = errbuf;
+					while ((line = strsep(&pos, "\n")))
+						if (pos || line[0] != '\0')
+							info(udev, "'%s' (stderr) '%s'\n", argv[0], line);
+				}
+			}
+			if (outpipe[READ_END] > 0)
+				close(outpipe[READ_END]);
+			if (errpipe[READ_END] > 0)
+				close(errpipe[READ_END]);
+
+			/* return the childs stdout string */
+			if (result) {
+				result[respos] = '\0';
+				dbg(udev, "result='%s'\n", result);
+				if (reslen)
+					*reslen = respos;
+			}
+		}
+		waitpid(pid, &status, 0);
+		if (WIFEXITED(status)) {
+			info(udev, "'%s' returned with status %i\n", argv[0], WEXITSTATUS(status));
+			if (WEXITSTATUS(status) != 0)
+				err = -1;
+		} else {
+			err(udev, "'%s' abnormal exit\n", command);
+			err = -1;
+		}
+	}
+	return err;
+}