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alfrebalfreb
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Merge pull request #1102 from ingve/posixstubs
posix: pwd-related functions
2 parents bae5b87 + a6c4ec9 commit 1ba220b

6 files changed

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‎src/CMakeLists.txt‎

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@@ -53,6 +53,7 @@ set(OS_OBJECTS
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posix/sys/socket.cpp posix/sys/select.cpp posix/sys/utsname.cpp posix/sys/mman.cpp posix/arpa/inet.cpp
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posix/ucontext.cpp posix/ucontext_asm.asm
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posix/sys/stat.cpp posix/ftw.cpp posix/file_fd.cpp posix/dlfcn.cpp
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posix/pwd.cpp
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)
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add_library(os STATIC ${OS_OBJECTS} apic_boot.o)

‎src/posix/pwd.cpp‎

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// This file is a part of the IncludeOS unikernel - www.includeos.org
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//
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// Copyright 2015-2017 Oslo and Akershus University College of Applied Sciences
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// and Alfred Bratterud
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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#include <string>
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#include <vector>
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#include <fstream>
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#include <pwd.h>
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#include <info>
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#include <gsl/gsl_assert>
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const char* pwd_path = "/etc/passwd";
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/* Applications are not allowed to modify the structure to which the return
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values point, nor any storage areas pointed to by pointers within the
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structure. Returned pointers might be invalidated or the structure/
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storage areas might be overwritten by subsequent calls. */
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static struct passwd ret;
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class Pwd {
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public:
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static Pwd& instance() {
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static Pwd pwd;
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return pwd;
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}
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void rewind() {pos_ = 0;}
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void close() {open_ = false;}
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struct passwd* find(const char* name) {
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Expects(name != nullptr);
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if (!open_) {
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read();
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}
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const auto it = std::find_if(begin(entries_), end(entries_), [name](const auto& entry){
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return (strcmp(name, entry.c_str()) == 0);
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});
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if (it == end(entries_)) {
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return nullptr;
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}
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extract(*it);
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return &ret;
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}
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struct passwd* next() noexcept {
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if (!open_) {
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read();
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}
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if (pos_ >= entries_.size()) {
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return nullptr;
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}
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try {
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const auto& ent = entries_[pos_];
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int field_seps = std::count(std::begin(ent), std::end(ent), '\0');
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if (field_seps != 6) {
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INFO("pwd", "not a valid passwd file entry");
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return nullptr;
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}
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extract(ent);
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++pos_;
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return &ret;
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}
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catch (...) {
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INFO("pwd", "error parsing pwd entry");
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return nullptr;
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}
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}
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void extract(const std::string& ent) {
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ret.pw_name = const_cast<char*>(ent.c_str());
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size_t pw_pos = ent.find('\0') + 1;
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size_t uid_pos = ent.find('\0', pw_pos) + 1;
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size_t gid_pos = ent.find('\0', uid_pos) + 1;
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size_t info_pos = ent.find('\0', gid_pos) + 1;
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size_t dir_pos = ent.find('\0', info_pos) + 1;
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size_t shell_pos = ent.find('\0', dir_pos) + 1;
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ret.pw_uid = std::stol(ret.pw_name + uid_pos);
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ret.pw_gid = std::stol(ret.pw_name + gid_pos);
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ret.pw_dir = ret.pw_name + dir_pos;
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ret.pw_shell = ret.pw_name + shell_pos;
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}
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void print() {
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printf(" instance @%p\n", this);
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printf(" open: %d\n", open_);
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printf(" pos: %d\n", pos_);
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printf(" entries: %d\n", entries_.size());
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}
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private:
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Pwd() : open_ {false}, pos_ {0} {}
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void read() {
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std::ifstream is(pwd_path);
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std::string line;
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while (std::getline(is, line)) {
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std::replace(std::begin(line), std::end(line), ':', '\0');
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entries_.push_back(line);
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}
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rewind();
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open_ = true;
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}
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bool open_;
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size_t pos_;
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std::vector<std::string> entries_;
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};
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void endpwent(void) {
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Pwd& pwd = Pwd::instance();
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pwd.close();
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}
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void setpwent(void) {
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Pwd& pwd = Pwd::instance();
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pwd.rewind();
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}
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struct passwd *getpwent(void) {
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Pwd& pwd = Pwd::instance();
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return pwd.next();
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}
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struct passwd *getpwnam(const char *name) {
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if (name == nullptr) {
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return nullptr;
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}
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Pwd& pwd = Pwd::instance();
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return pwd.find(name);
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}

‎test/posix/integration/conf/CMakeLists.txt‎

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@@ -24,6 +24,7 @@ set(SOURCES
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service.cpp
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test_sysconf.c
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test_pathconf.c
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test_pwd.c
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)
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# DRIVERS / PLUGINS:

‎test/posix/integration/conf/disk/passwd‎

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@@ -1 +1,5 @@
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nobody:*:-2:-2:Unprivileged User:/var/empty:/usr/bin/false
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root:*:0:0:System Administrator:/var/root:/bin/sh
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daemon:*:1:1:System Services:/var/root:/usr/bin/false
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_ftp:*:98:-2:FTP Daemon:/var/empty:/usr/bin/false
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_launchservicesd:*:239:239:_launchservicesd:/var/empty:/usr/bin/false

‎test/posix/integration/conf/service.cpp‎

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@@ -27,6 +27,7 @@
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extern "C" void test_sysconf();
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extern "C" void test_pathconf();
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extern "C" void test_pwd();
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fs::Disk_ptr& memdisk() {
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static auto disk = fs::new_shared_memdisk();
@@ -74,5 +75,8 @@ int main(int argc, char *argv[]) {
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value = getenv("INCLUDEOS_CORE_DUMP");
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printf("INCLUDEOS_CORE_DUMP: %s\n", value);
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// test pwd-related functions
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test_pwd();
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INFO("Conf", "SUCCESS");
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}

‎test/posix/integration/conf/test_pwd.c‎

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// This file is a part of the IncludeOS unikernel - www.includeos.org
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//
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// Copyright 2015-2017 Oslo and Akershus University College of Applied Sciences
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// and Alfred Bratterud
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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#include <pwd.h>
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#include <stdio.h>
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void print_pwd_entry(struct passwd* pwd_ent);
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void test_pwd() {
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struct passwd* pwd_ent;
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while((pwd_ent = getpwent()) != NULL) {
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print_pwd_entry(pwd_ent);
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}
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printf("Back to start!\n");
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setpwent();
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pwd_ent = getpwent();
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print_pwd_entry(pwd_ent);
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endpwent();
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pwd_ent = getpwnam("root");
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if (pwd_ent != NULL) {
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print_pwd_entry(pwd_ent);
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}
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pwd_ent = getpwnam("alfred");
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if (pwd_ent != NULL) {
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print_pwd_entry(pwd_ent);
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}
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}
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void print_pwd_entry(struct passwd* pwd_ent) {
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printf("Name: %s\n", pwd_ent->pw_name);
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printf("Uid: %d\n", pwd_ent->pw_uid);
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printf("Gid: %d\n", pwd_ent->pw_gid);
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printf("Path: %s\n", pwd_ent->pw_dir);
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printf("Shell: %s\n\n", pwd_ent->pw_shell);
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}

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