Shell: $(...) expansion works now :)

This commit is contained in:
Bananymous 2023-07-06 23:22:57 +03:00
parent ad98181069
commit 683c2a68cd
1 changed files with 84 additions and 8 deletions

View File

@ -11,12 +11,16 @@
#include <termios.h>
#include <unistd.h>
#define ERROR_RETURN(msg) { perror(msg); return 1; }
#define ERROR_RETURN(__msg, __ret) do { perror(__msg); return __ret; } while (false)
struct termios old_termios, new_termios;
extern char** environ;
static const char* argv0 = nullptr;
BAN::Vector<BAN::String> parse_command(BAN::StringView);
BAN::Optional<BAN::String> parse_dollar(BAN::StringView command, size_t& i)
{
ASSERT(command[i] == '$');
@ -64,7 +68,77 @@ BAN::Optional<BAN::String> parse_dollar(BAN::StringView command, size_t& i)
}
else if (command[i] == '(')
{
size_t len = 1;
int count = 1;
for (; i + len < command.size(); len++)
{
if (command[i + len] == '(')
count++;
if (command[i + len] == ')')
count--;
if (count == 0)
break;
}
if (count != 0)
return {};
BAN::String subcommand = command.substring(i + 1, len - 1);
char temp[3] { '-', 'c', '\0' };
BAN::Vector<char*> argv;
MUST(argv.push_back((char*)argv0));
MUST(argv.push_back(temp));
MUST(argv.push_back((char*)subcommand.data()));
MUST(argv.push_back(nullptr));
int fds[2];
if (pipe(fds) == -1)
ERROR_RETURN("pipe", {});
pid_t pid = fork();
if (pid == 0)
{
if (dup2(fds[1], STDOUT_FILENO) == -1)
{
perror("dup2");
exit(1);
}
close(fds[0]);
close(fds[1]);
execv(argv.front(), argv.data());
perror("execv");
exit(1);
}
if (pid == -1)
ERROR_RETURN("fork", {});
close(fds[1]);
char buffer[100];
BAN::String output;
while (ssize_t ret = read(fds[0], buffer, sizeof(buffer)))
{
if (ret == -1)
{
perror("read");
break;
}
MUST(output.append(BAN::StringView(buffer, ret)));
}
close(fds[0]);
int status;
if (waitpid(pid, &status, 0) == -1 && errno != ECHILD)
ERROR_RETURN("waitpid", {});
while (!output.empty() && output.back() == '\n')
output.pop_back();
i += len;
return output;
}
return "$"sv;
@ -177,7 +251,7 @@ int execute_command(BAN::Vector<BAN::String>& args)
continue;
if (setenv(BAN::String(split[0]).data(), BAN::String(split[1]).data(), true) == -1)
ERROR_RETURN("setenv");
ERROR_RETURN("setenv", 1);
}
}
else if (args.front() == "env"sv)
@ -207,7 +281,7 @@ int execute_command(BAN::Vector<BAN::String>& args)
path = args[1];
if (chdir(path.data()) == -1)
ERROR_RETURN("chdir");
ERROR_RETURN("chdir", 1);
}
else if (args.front() == "time"sv)
{
@ -216,12 +290,12 @@ int execute_command(BAN::Vector<BAN::String>& args)
timespec start, end;
if (clock_gettime(CLOCK_MONOTONIC, &start) == -1)
ERROR_RETURN("clock_gettime");
ERROR_RETURN("clock_gettime", 1);
int ret = execute_command(args);
if (clock_gettime(CLOCK_MONOTONIC, &end) == -1)
ERROR_RETURN("clock_gettime");
ERROR_RETURN("clock_gettime", 1);
uint64_t total_ns = 0;
total_ns += (end.tv_sec - start.tv_sec) * 1'000'000'000;
@ -250,11 +324,11 @@ int execute_command(BAN::Vector<BAN::String>& args)
exit(1);
}
if (pid == -1)
ERROR_RETURN("fork");
ERROR_RETURN("fork", 1);
int status;
if (waitpid(pid, &status, 0) == -1)
ERROR_RETURN("waitpid");
ERROR_RETURN("waitpid", 1);
return status;
}
@ -359,6 +433,8 @@ void print_prompt()
int main(int argc, char** argv)
{
argv0 = argv[0];
if (argc >= 2)
{
if (strcmp(argv[1], "-c") == 0)