joseph-aquino
/
shell
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

fixed rediriction and appending stdout and stderr on linux, still need to test on windows

This commit is contained in:
Joseph Aquino 2026-01-05 10:49:59 -05:00
parent bf8a78bc84
commit e100cd15d1
3 changed files with 183 additions and 54 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
include/shellUtils.h
View File

@ -6,6 +6,7 @@
#include <cstdlib>
#include <filesystem>
#include <vector>
#include <optional>
namespace sh
{
@ -39,15 +40,15 @@ namespace sh
std::optional<std::filesystem::path> isExec(const std::string& input);
void printType(const std::string& input);
void printType(const std::string& input, const std::optional<std::filesystem::path>& stdoutFilePath = std::nullopt);
std::filesystem::path getWorkingDir();
void changeDir(const std::vector<std::string>& tokens);
void changeDir(const std::vector<std::string>& tokens, const std::optional<std::filesystem::path>& stdoutFilePath = std::nullopt);
void printCommandStdout(std::string_view input, const std::optional<std::filesystem::path>& outputFilePath = std::nullopt);
void printCommandStdout(std::string_view input, const std::optional<std::filesystem::path>& outputFilePath = std::nullopt, bool append = false);
void printCommandStderr(std::string_view input, const std::optional<std::filesystem::path>& outputFilePath = std::nullopt);
void printCommandStderr(std::string_view input, const std::optional<std::filesystem::path>& outputFilePath = std::nullopt, bool append = false);
void executeCommand(const std::filesystem::path& exePath, const std::vector<std::string>& tokens, const std::optional<std::filesystem::path>& outputFilePath = std::nullopt);
void executeCommand(const std::filesystem::path& exePath, const std::vector<std::string>& tokens, const std::optional<std::filesystem::path>& stdoutFilePath = std::nullopt, const std::optional<std::filesystem::path>& stderrFilePath = std::nullopt, bool appendStdout = false, bool appendStderr = false);
}

85
src/main.cpp
View File

@ -2,8 +2,9 @@
#include <string>
#include <cstdlib>
#include <filesystem>
#include <fstream>
#include <vector>
#include <optional>
#include "shellUtils.h"
@ -11,7 +12,6 @@
int main()
{
std::vector<std::string> tokens;
std::optional<std::filesystem::path> stdoutFile;
std::cout << std::unitbuf;
std::cerr << std::unitbuf;
@ -20,6 +20,10 @@ int main()
while (!shouldExit)
{
tokens.clear();
std::optional<std::filesystem::path> stdoutFile;
std::optional<std::filesystem::path> stderrFile;
bool appendStdout{false};
bool appendStderr{false};
std::string input;
std::string line;
@ -29,6 +33,12 @@ int main()
while (!finshedInput and std::getline(std::cin, line))
{
if (line.empty())
{
finshedInput = true;
continue;
}
auto end = line.size() - 1;
if (line[end] == '\\')
{
@ -70,19 +80,64 @@ int main()
sh::tokenize(tokens, input);
//check for redirection
for (size_t i = 0; i < tokens.size(); i++)
for (size_t i = 0; i < tokens.size();)
{
if (tokens[i] == ">")
if (tokens[i] == ">>" or tokens[i] == "1>>")
{
if (i + 1 >= tokens.size())
{
std::cerr << "Syntax error: expeceted filepath after '>>'\n";
continue;
}
appendStdout = true;
stdoutFile = tokens[i+1];
tokens.erase(tokens.begin() + i, tokens.begin() + i + 2);
continue;
}
if (tokens[i] == "2>>")
{
if (i + 1 >= tokens.size())
{
std::cerr << "Syntax error: expeceted filepath after '>>'\n";
continue;
}
appendStderr = true;
stderrFile = tokens[i+1];
tokens.erase(tokens.begin() + i, tokens.begin() + i + 2);
continue;
}
if (tokens[i] == ">" or tokens[i] == "1>")
{//stdout redirect
if (i + 1 >= tokens.size())
{//if no output specified, just remove and continue as normal
tokens.erase(tokens.begin() + i, tokens.begin() + i + 1);
std::cerr << "Syntax error: expeceted filepath after '>'\n";
continue;
}
stdoutFile = tokens[i+1];
tokens.erase(tokens.begin() + i, tokens.begin() + i + 2);
continue;
}
if (tokens[i] == "2>")
{//stdout redirect
if (i + 1 >= tokens.size())
{//if no output specified, just remove and continue as normal
std::cerr << "Syntax error: expeceted filepath after '>'\n";
continue;
}
stderrFile = tokens[i+1];
tokens.erase(tokens.begin() + i, tokens.begin() + i + 2);
continue;
}
i++;
}
std::optional<std::filesystem::path> result;
@ -94,13 +149,18 @@ int main()
shouldExit = true;
break;
case sh::Command::echo:
if (stderrFile)
{
std::ofstream err{stderrFile.value()};
err.close();
}
for (int i = 1; i < tokens.size(); i++)
{
output << tokens[i] << " ";
output << tokens[i];
if (i < tokens.size() - 1) output << " ";
}
output << "\n";
stdoutFile ?
sh::printCommandStdout(output.str(), stdoutFile.value()) :
sh::printCommandStdout(output.str(), stdoutFile.value(), appendStdout) :
sh::printCommandStdout(output.str());
break;
@ -108,25 +168,24 @@ int main()
result = sh::isExec(tokens[0]);
if (result)
{
sh::executeCommand(result.value(), tokens, stdoutFile);
sh::executeCommand(result.value(), tokens, stdoutFile, stderrFile, appendStdout, appendStderr);
}
else
{
output << tokens[0] << ": command not found\n";
output << tokens[0] << ": command not found";
stdoutFile ?
sh::printCommandStdout(output.str(), stdoutFile.value()) :
sh::printCommandStdout(output.str());
}
break;
case sh::Command::type:
sh::printType(tokens[1]);
sh::printType(tokens[1], stdoutFile);
break;
case sh::Command::pwd:
std::cout << std::filesystem::current_path().string() << "\n";
break;
case sh::Command::cd:
sh::changeDir(tokens);
sh::changeDir(tokens, stdoutFile);
break;
}
}

141
src/shellUtils.cpp
View File

@ -136,36 +136,36 @@ namespace sh
return std::nullopt;
}
void printType(const std::string& input, const std::optional<std::filesystem::path>& outputPath)
void printType(const std::string& input, const std::optional<std::filesystem::path>& stdoutFilePath)
{
std::ostringstream output;
if (commandMap.contains(input))
{
output << input << " is a shell builtin\n";
output << input << " is a shell builtin";
}
else if (const auto fullPath {isExec(input)})
{
output << input;
output << " is " << fullPath.value().string() << "\n";
output << " is " << fullPath.value().string();
}
else
{
output << input;
output << ": not found\n";
output << ": not found";
}
outputPath ?
printCommandStdout(output.str(), outputPath.value()) :
stdoutFilePath ?
printCommandStdout(output.str(), stdoutFilePath.value()) :
printCommandStdout(output.str());
}
void changeDir(const std::vector<std::string>& tokens, const std::optional<std::filesystem::path>& outputPath)
void changeDir(const std::vector<std::string>& tokens, const std::optional<std::filesystem::path>& stdoutFilePath)
{
if (tokens.size() > 2)
{
outputPath.has_value() ?
printCommandStderr("cd: too many arguments\n", outputPath.value()) :
printCommandStderr("cd: too many arguments\n");
stdoutFilePath.has_value() ?
printCommandStderr("cd: too many arguments", stdoutFilePath.value()) :
printCommandStderr("cd: too many arguments");
return;
}
@ -207,25 +207,27 @@ namespace sh
else
{
std::ostringstream output;
output << "cd: " << expandedPath.string() << ": No such file or directory\n";
output << "cd: " << expandedPath.string() << ": No such file or directory";
outputPath.has_value() ?
printCommandStderr(output.str(), outputPath.value()) :
stdoutFilePath.has_value() ?
printCommandStderr(output.str(), stdoutFilePath.value()) :
printCommandStderr(output.str());
}
}
void printCommandStdout(const std::string_view input, const std::optional<std::filesystem::path>& outputFilePath)
void printCommandStdout(const std::string_view input, const std::optional<std::filesystem::path>& stdoutFilePath, bool append)
{
if (outputFilePath)
if (stdoutFilePath)
{
std::ofstream output {outputFilePath.value()};
auto mode = append ? std::ios::app : std::ios::trunc;
std::ofstream output {stdoutFilePath.value(), mode};
if (!output)
{
std::cerr << "ERROR: cannot open " << outputFilePath.value().string() << "\n";
std::cerr << "ERROR: cannot open " << stdoutFilePath.value().string() << "\n";
}
output << input;
output << input << "\n";
output.close();
return;
}
@ -233,14 +235,16 @@ namespace sh
std::cout << input << "\n";
}
void printCommandStderr(const std::string_view input, const std::optional<std::filesystem::path>& outputFilePath)
void printCommandStderr(const std::string_view input, const std::optional<std::filesystem::path>& stderrFilePath, bool append)
{
if (outputFilePath)
if (stderrFilePath)
{
std::ofstream output {outputFilePath.value()};
auto mode = append ? std::ios::app : std::ios::trunc;
std::ofstream output {stderrFilePath.value(), mode};
if (!output)
{
std::cerr << "ERROR: cannot open " << outputFilePath.value().string() << "\n";
std::cerr << "ERROR: cannot open " << stderrFilePath.value().string() << "\n";
}
output << input;
output.close();
@ -250,7 +254,7 @@ namespace sh
std::cerr << input << "\n";
}
void executeCommand(const std::filesystem::path& exePath,const std::vector<std::string>& tokens, const std::optional<std::filesystem::path>& outputFilePath)
void executeCommand(const std::filesystem::path& exePath,const std::vector<std::string>& tokens, const std::optional<std::filesystem::path>& stdoutFilePath, const std::optional<std::filesystem::path>& stderrFilePath, bool appendStdout, bool appendStderr)
{
std::string filename = exePath.filename().string();
std::string fullPath = exePath.string();
@ -266,38 +270,72 @@ namespace sh
args.push_back(nullptr);
int originalStdout = -1;
int fileFd = -1;
int originalStderr = -1;
int stdoutFd = -1;
int stderrFd = -1;
if (outputFilePath)
if (stdoutFilePath)
{
originalStdout = _dup(1); // save out connection to the shell
fileFd = _open(outputFilePath.value().c_str(), _O_WRONGLY | _O_CREAT | _O_TRUNC, _S_IWRITE);
if (appendStdout)
{
stdoutFd = _open(stdoutFilePath.value().c_str(), _O_WRONLY | _O_CREAT, _S_IWRITE);
}
else
{
stdoutFd = _open(stdoutFilePath.value().c_str(), _O_WRONLY | _O_CREAT | _O_TRUNC, _S_IWRITE);
}
if (fileFd == -1)
if (stdoutFd == -1)
{
perror("Could not open redirect file\n");
_close(originalStdout);
return;
_dup2(fileFd, 1);
}
_dup2(stdoutFd, 1);
}
if (stderrFilePath)
{
originalStderr = _dup(2);
if (appendStderr)
{
stderrFd = _open(stderrFilePath.value().c_str(), _O_WRONLY | _O_CREAT | _O_APPEND, _S_IWRITE);
}
else
{
stderrFd = _open(stderrFilePath.value().c_str(), _O_WRONLY | _O_CREAT | _O_TRUNC, _S_IWRITE);
}
if (stderrFd == -1)
{
perror("could not redirect stderr to file");
return;
}
_dup2(stderrFd, 2);
}
intptr_t status = _spawnv(_P_WAIT, fullPath.c_str(), args.data());
if (outputFilePath)
if (stdoutFilePath)
{
_dup2(originalStdout, 1);
_close(originalStdout);
_close(fileFd);
_close(stdoutFd);
}
if (stderrFilePath)
{
_dup2(originalStderr, 2);
_close(originalStderr);
_close(stderrFd);
}
if (status == -1)
{
perror("\n\nError executing program\n\n");
return 1;
return;
}
#else
std::vector<char*> args;
@ -312,9 +350,17 @@ namespace sh
pid_t pid = fork();
if (pid == 0)
{// child process
if (outputFilePath)
if (stdoutFilePath)
{
int fileFd = open(outputFilePath.value().c_str(), O_WRONLY | O_CREAT | O_TRUNC, 0644);// 0644: Permissions (rw-r--r--)
int fileFd;
if (appendStdout)
{
fileFd = open(stdoutFilePath.value().c_str(), O_WRONLY | O_CREAT | O_APPEND, 0644);// 0644: Permissions (rw-r--r--)
}
else
{
fileFd = open(stdoutFilePath.value().c_str(), O_WRONLY | O_CREAT | O_TRUNC, 0644);// 0644: Permissions (rw-r--r--)
}
if (fileFd == -1)
{
@ -322,7 +368,30 @@ namespace sh
exit(1);
}
dup2(fileFd, STDIN_FILENO);
dup2(fileFd, STDOUT_FILENO);
close(fileFd);
}
if (stderrFilePath)
{
int fileFd;
if (appendStderr)
{
fileFd = open(stderrFilePath.value().c_str(), O_WRONLY | O_CREAT| O_APPEND, 0644);// 0644: Permissions (rw-r--r--)
}
else
{
fileFd = open(stderrFilePath.value().c_str(), O_WRONLY | O_CREAT | O_TRUNC, 0644);// 0644: Permissions (rw-r--r--)
}
if (fileFd == -1)
{
perror("Error opening redirect file\n");
exit(1);
}
dup2(fileFd, STDERR_FILENO);
close(fileFd);
}