feat(userspace/libc): implement <pwd.h> header

Implemented everything except endpwent() and setpwent()

NOT TESTED!

Signed-off-by: EnderIce2 <enderice2@protonmail.com>

Userspace/libc/include/pwd.h

@@ -25,21 +25,43 @@ extern "C"
 
 #include <sys/types.h>
 
+	/**
+	 * /etc/passwd
+	 *    name:passwd:uid:gid:gecos:dir:shell
+	 *
+	 * Example
+	 *
+	 *    root:x:0:0:root:/root:/bin/sh
+	 *      |  | | |  |     |      |
+	 *      |  | | |  |     |      \-- pw_shell
+	 *      |  | | |  |     \-- pw_dir
+	 *      |  | | |  \-- pw_gecos
+	 *      |  | | \-- pw_gid
+	 *      |  | \-- pw_uid
+	 *      |  \-- pw_passwd
+	 *      \-- pw_name
+	 *
+	 * @ref https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/pwd.h.html
+	 * @ref https://man7.org/linux/man-pages/man3/getpw.3.html
+	 * @ref https://man7.org/linux/man-pages/man5/passwd.5.html
+	 */
 	struct passwd
 	{
-		char *pw_name;	/* User's login name. */
+		char *pw_name;	 /* User's login name. */
-		uid_t pw_uid;	/* Numerical user ID. */
+		char *pw_passwd; /* User password. */
-		gid_t pw_gid;	/* Numerical group ID. */
+		uid_t pw_uid;	 /* Numerical user ID. */
-		char *pw_dir;	/* Initial working directory. */
+		gid_t pw_gid;	 /* Numerical group ID. */
-		char *pw_shell; /* Program to use as shell. */
+		char *pw_gecos;	 /* User information. */
+		char *pw_dir;	 /* Initial working directory. */
+		char *pw_shell;	 /* Program to use as shell. */
 	};
 
 	void endpwent(void);
 	struct passwd *getpwent(void);
-	struct passwd *getpwnam(const char *);
+	struct passwd *getpwnam(const char *name);
-	int getpwnam_r(const char *, struct passwd *, char *, size_t, struct passwd **);
+	int getpwnam_r(const char *name, struct passwd *pwd, char *buffer, size_t bufsize, struct passwd **result);
-	struct passwd *getpwuid(uid_t);
+	struct passwd *getpwuid(uid_t uid);
-	int getpwuid_r(uid_t, struct passwd *, char *, size_t, struct passwd **);
+	int getpwuid_r(uid_t uid, struct passwd *pwd, char *buffer, size_t bufsize, struct passwd **result);
 	void setpwent(void);
 
 #ifdef __cplusplus

Userspace/libc/src/std/pwd.c

@@ -0,0 +1,151 @@
+/*
+	This file is part of Fennix C Library.
+
+	Fennix C Library 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 3 of
+	the License, or (at your option) any later version.
+
+	Fennix C Library 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 Fennix C Library. If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#include <pwd.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+export void endpwent(void)
+{
+	/* FIXME */
+}
+
+export struct passwd *getpwent(void)
+{
+	static FILE *pwfile = NULL;
+	static struct passwd pwd;
+	static char line[256];
+
+	if (pwfile == NULL)
+	{
+		pwfile = fopen("/etc/passwd", "r");
+		if (pwfile == NULL)
+			return NULL;
+	}
+
+	if (fgets(line, sizeof(line), pwfile) == NULL)
+	{
+		fclose(pwfile);
+		pwfile = NULL;
+		return NULL;
+	}
+
+	char *token = strtok(line, ":");
+	pwd.pw_name = token;
+
+	token = strtok(NULL, ":");
+	pwd.pw_passwd = token;
+
+	token = strtok(NULL, ":");
+	pwd.pw_uid = atoi(token);
+
+	token = strtok(NULL, ":");
+	pwd.pw_gid = atoi(token);
+
+	token = strtok(NULL, ":");
+	pwd.pw_gecos = token;
+
+	token = strtok(NULL, ":");
+	pwd.pw_dir = token;
+
+	token = strtok(NULL, ":");
+	pwd.pw_shell = token;
+
+	return &pwd;
+}
+
+export struct passwd *getpwnam(const char *name)
+{
+	struct passwd *pwd;
+	setpwent();
+	while ((pwd = getpwent()) != NULL)
+	{
+		if (strcmp(pwd->pw_name, name) == 0)
+		{
+			endpwent();
+			return pwd;
+		}
+	}
+	endpwent();
+	return NULL;
+}
+
+export int getpwnam_r(const char *name, struct passwd *pwd, char *buffer, size_t bufsize, struct passwd **result)
+{
+	FILE *pwfile;
+	char line[256];
+	struct passwd *pwd_entry;
+
+	setpwent();
+	while ((pwd_entry = getpwent()) != NULL)
+	{
+		if (strcmp(pwd_entry->pw_name, name) == 0)
+		{
+			*pwd = *pwd_entry;
+			*result = pwd;
+			endpwent();
+			return 0;
+		}
+	}
+	endpwent();
+	*result = NULL;
+	return 0;
+}
+
+export struct passwd *getpwuid(uid_t uid)
+{
+	struct passwd *pwd;
+	setpwent();
+	while ((pwd = getpwent()) != NULL)
+	{
+		if (pwd->pw_uid == uid)
+		{
+			endpwent();
+			return pwd;
+		}
+	}
+	endpwent();
+	return NULL;
+}
+
+export int getpwuid_r(uid_t uid, struct passwd *pwd, char *buffer, size_t bufsize, struct passwd **result)
+{
+	FILE *pwfile;
+	char line[256];
+	struct passwd *pwd_entry;
+
+	setpwent();
+	while ((pwd_entry = getpwent()) != NULL)
+	{
+		if (pwd_entry->pw_uid == uid)
+		{
+			*pwd = *pwd_entry;
+			*result = pwd;
+			endpwent();
+			return 0;
+		}
+	}
+	endpwent();
+	*result = NULL;
+	return 0;
+}
+
+export void setpwent(void)
+{
+	/* FIXME */
+}