mirror of
https://github.com/LadybirdBrowser/ladybird.git
synced 2025-04-21 12:05:15 +00:00
sh: Add support for redirecting stdin and stdout with < and >.
This is certainly about time. The kernel has had all the necessary support in place for months, and I just kept postponing working on the shell. :^)
This commit is contained in:
Andreas Kling
parent
df8e76a67c
commit
04b7def6ab
Notes:
sideshowbarker
2024-07-19 14:35:34 +09:00
Author: https://github.com/awesomekling Commit: https://github.com/SerenityOS/serenity/commit/04b7def6ab2
1 changed files with 112 additions and 20 deletions
132
Userland/sh.cpp
132
Userland/sh.cpp
|
|
@ -12,6 +12,8 @@
|
|||
#include <sys/utsname.h>
|
||||
#include <AK/FileSystemPath.h>
|
||||
|
||||
//#define SH_DEBUG
|
||||
|
||||
struct GlobalState {
|
||||
String cwd;
|
||||
String username;
|
||||
|
|
@ -120,10 +122,11 @@ static bool handle_builtin(int argc, char** argv, int& retval)
|
|||
}
|
||||
|
||||
struct Redirection {
|
||||
enum Type { Pipe, File, Rewire };
|
||||
enum Type { Pipe, FileWrite, FileRead, Rewire };
|
||||
Type type;
|
||||
int fd { -1 };
|
||||
int rewire_fd { -1 };
|
||||
String path { };
|
||||
};
|
||||
|
||||
struct Subcommand {
|
||||
|
|
@ -141,7 +144,8 @@ private:
|
|||
void commit_token();
|
||||
void commit_subcommand();
|
||||
void do_pipe();
|
||||
void begin_redirect_fd(int fd);
|
||||
void begin_redirect_read(int fd);
|
||||
void begin_redirect_write(int fd);
|
||||
|
||||
enum State {
|
||||
Free,
|
||||
|
|
@ -162,6 +166,11 @@ void Parser::commit_token()
|
|||
{
|
||||
if (m_token.is_empty())
|
||||
return;
|
||||
if (m_state == InRedirectionPath) {
|
||||
m_redirections.last().path = String::copy(m_token);
|
||||
m_token.clear_with_capacity();
|
||||
return;
|
||||
}
|
||||
m_tokens.append(String::copy(m_token));
|
||||
m_token.clear_with_capacity();
|
||||
};
|
||||
|
|
@ -179,9 +188,14 @@ void Parser::do_pipe()
|
|||
commit_subcommand();
|
||||
}
|
||||
|
||||
void Parser::begin_redirect_fd(int fd)
|
||||
void Parser::begin_redirect_read(int fd)
|
||||
{
|
||||
m_redirections.append({ Redirection::File, fd });
|
||||
m_redirections.append({ Redirection::FileRead, fd });
|
||||
}
|
||||
|
||||
void Parser::begin_redirect_write(int fd)
|
||||
{
|
||||
m_redirections.append({ Redirection::FileWrite, fd });
|
||||
}
|
||||
|
||||
Vector<Subcommand> Parser::parse()
|
||||
|
|
@ -204,12 +218,14 @@ Vector<Subcommand> Parser::parse()
|
|||
break;
|
||||
}
|
||||
if (ch == '>') {
|
||||
begin_redirect_fd(STDOUT_FILENO);
|
||||
commit_token();
|
||||
begin_redirect_write(STDOUT_FILENO);
|
||||
m_state = State::InRedirectionPath;
|
||||
break;
|
||||
}
|
||||
if (ch == '<') {
|
||||
begin_redirect_fd(STDIN_FILENO);
|
||||
commit_token();
|
||||
begin_redirect_read(STDIN_FILENO);
|
||||
m_state = State::InRedirectionPath;
|
||||
break;
|
||||
}
|
||||
|
|
@ -224,10 +240,31 @@ Vector<Subcommand> Parser::parse()
|
|||
m_token.append(ch);
|
||||
break;
|
||||
case State::InRedirectionPath:
|
||||
if (ch == ' ') {
|
||||
if (ch == '<') {
|
||||
commit_token();
|
||||
begin_redirect_read(STDIN_FILENO);
|
||||
m_state = State::InRedirectionPath;
|
||||
break;
|
||||
}
|
||||
if (ch == '>') {
|
||||
commit_token();
|
||||
begin_redirect_read(STDOUT_FILENO);
|
||||
m_state = State::InRedirectionPath;
|
||||
break;
|
||||
}
|
||||
if (ch == '|') {
|
||||
commit_token();
|
||||
if (m_tokens.is_empty()) {
|
||||
fprintf(stderr, "Syntax error: Nothing before pipe (|)\n");
|
||||
return { };
|
||||
}
|
||||
do_pipe();
|
||||
m_state = State::Free;
|
||||
break;
|
||||
}
|
||||
if (ch == ' ')
|
||||
break;
|
||||
m_token.append(ch);
|
||||
break;
|
||||
case State::InSingleQuotes:
|
||||
if (ch == '\'') {
|
||||
|
|
@ -262,6 +299,23 @@ Vector<Subcommand> Parser::parse()
|
|||
return move(m_subcommands);
|
||||
}
|
||||
|
||||
class FileDescriptorCollector {
|
||||
public:
|
||||
FileDescriptorCollector() { }
|
||||
~FileDescriptorCollector() { collect(); }
|
||||
|
||||
void collect()
|
||||
{
|
||||
for (auto fd : m_fds)
|
||||
close(fd);
|
||||
m_fds.clear();
|
||||
}
|
||||
void add(int fd) { m_fds.append(fd); }
|
||||
|
||||
private:
|
||||
Vector<int, 32> m_fds;
|
||||
};
|
||||
|
||||
static int runcmd(char* cmd)
|
||||
{
|
||||
if (cmd[0] == 0)
|
||||
|
|
@ -271,21 +325,39 @@ static int runcmd(char* cmd)
|
|||
|
||||
auto subcommands = Parser(cmd).parse();
|
||||
|
||||
#ifdef PARSE_DEBUG
|
||||
#ifdef SH_DEBUG
|
||||
for (int i = 0; i < subcommands.size(); ++i) {
|
||||
for (int j = 0; j < i; ++j)
|
||||
printf(" ");
|
||||
printf(" ");
|
||||
for (auto& arg : subcommands[i].args) {
|
||||
printf("<%s> ", arg.characters());
|
||||
}
|
||||
printf("\n");
|
||||
for (auto& redirecton : subcommands[i].redirections) {
|
||||
for (int j = 0; j < i; ++j)
|
||||
printf(" ");
|
||||
printf(" ");
|
||||
switch (redirecton.type) {
|
||||
case Redirection::Pipe:
|
||||
printf("Pipe\n");
|
||||
break;
|
||||
case Redirection::FileRead:
|
||||
printf("fd:%d = FileRead: %s\n", redirecton.fd, redirecton.path.characters());
|
||||
break;
|
||||
case Redirection::FileWrite:
|
||||
printf("fd:%d = FileWrite: %s\n", redirecton.fd, redirecton.path.characters());
|
||||
break;
|
||||
default:
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
#endif
|
||||
|
||||
if (subcommands.is_empty())
|
||||
return 0;
|
||||
|
||||
Vector<int> fds;
|
||||
FileDescriptorCollector fds;
|
||||
|
||||
for (int i = 0; i < subcommands.size(); ++i) {
|
||||
auto& subcommand = subcommands[i];
|
||||
|
|
@ -300,8 +372,26 @@ static int runcmd(char* cmd)
|
|||
subcommand.redirections.append({ Redirection::Rewire, STDOUT_FILENO, pipefd[1] });
|
||||
auto& next_command = subcommands[i + 1];
|
||||
next_command.redirections.append({ Redirection::Rewire, STDIN_FILENO, pipefd[0] });
|
||||
fds.append(pipefd[0]);
|
||||
fds.append(pipefd[1]);
|
||||
fds.add(pipefd[0]);
|
||||
fds.add(pipefd[1]);
|
||||
}
|
||||
if (redirection.type == Redirection::FileWrite) {
|
||||
int fd = open(redirection.path.characters(), O_WRONLY | O_CREAT, 0666);
|
||||
if (fd < 0) {
|
||||
perror("open");
|
||||
return 1;
|
||||
}
|
||||
subcommand.redirections.append({ Redirection::Rewire, redirection.fd, fd });
|
||||
fds.add(fd);
|
||||
}
|
||||
if (redirection.type == Redirection::FileRead) {
|
||||
int fd = open(redirection.path.characters(), O_RDONLY);
|
||||
if (fd < 0) {
|
||||
perror("open");
|
||||
return 1;
|
||||
}
|
||||
subcommand.redirections.append({ Redirection::Rewire, redirection.fd, fd });
|
||||
fds.add(fd);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
|
@ -319,7 +409,7 @@ static int runcmd(char* cmd)
|
|||
argv.append(nullptr);
|
||||
|
||||
int retval = 0;
|
||||
if (handle_builtin(argv.size() - 1, (char**)argv.data(), retval))
|
||||
if (handle_builtin(argv.size() - 1, const_cast<char**>(argv.data()), retval))
|
||||
return retval;
|
||||
|
||||
pid_t child = fork();
|
||||
|
|
@ -328,7 +418,9 @@ static int runcmd(char* cmd)
|
|||
tcsetpgrp(0, getpid());
|
||||
for (auto& redirection : subcommand.redirections) {
|
||||
if (redirection.type == Redirection::Rewire) {
|
||||
#ifdef SH_DEBUG
|
||||
dbgprintf("in %s<%d>, dup2(%d, %d)\n", argv[0], getpid(), redirection.rewire_fd, redirection.fd);
|
||||
#endif
|
||||
int rc = dup2(redirection.rewire_fd, redirection.fd);
|
||||
if (rc < 0) {
|
||||
perror("dup2");
|
||||
|
|
@ -337,10 +429,9 @@ static int runcmd(char* cmd)
|
|||
}
|
||||
}
|
||||
|
||||
for (auto& fd : fds)
|
||||
close(fd);
|
||||
fds.collect();
|
||||
|
||||
int rc = execvp(argv[0], (char* const*)argv.data());
|
||||
int rc = execvp(argv[0], const_cast<char* const*>(argv.data()));
|
||||
if (rc < 0) {
|
||||
perror("execvp");
|
||||
exit(1);
|
||||
|
|
@ -350,13 +441,14 @@ static int runcmd(char* cmd)
|
|||
children.append(child);
|
||||
}
|
||||
|
||||
#ifdef SH_DEBUG
|
||||
dbgprintf("Closing fds in shell process:\n");
|
||||
for (auto& fd : fds) {
|
||||
dbgprintf(" %d\n", fd);
|
||||
close(fd);
|
||||
}
|
||||
#endif
|
||||
fds.collect();
|
||||
|
||||
#ifdef SH_DEBUG
|
||||
dbgprintf("Now we gotta wait on children:\n");
|
||||
#endif
|
||||
for (auto& child : children)
|
||||
dbgprintf(" %d\n", child);
|
||||
|
||||
|
|
|
|||
Loading…
Add table
Reference in a new issue