header only lib

2024-05-17 19:02:56 +03:00
parent a8fb5f7d3d
commit 57c0aa4309
10 changed files with 272 additions and 264 deletions
@@ -0,0 +1,187 @@
+#include <iostream>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <errno.h>
+#include <cstring>
+#include "childProcess.hpp"
+
+
+inline RetProc::RetProc(Proc origin, int status)
+	: Proc(origin)
+	, normal_exit(WIFEXITED(status))
+	, returned(WEXITSTATUS(status))
+{}
+
+inline RetProc::operator bool()
+{
+	return normal_exit && returned == 0;
+}
+
+inline RetProc wait(Proc p)
+{
+	int status;
+	waitpid(p.pid, &status, 0);
+	return RetProc(p, status);
+}
+
+namespace _cppipe
+{
+	/* create a process taking input from pipe childIn */
+	inline Proc createProc(const char* const argv[], const fd_t childIn[2])
+	{
+		Proc childproc;
+		childproc.in = childIn[1];
+		childproc.out = STDOUT_FILENO;
+
+		childproc.pid = fork();
+		if(childproc.pid == 0)	/* child */
+		{
+			close(childIn[1]);
+			dup2(childIn[0], STDIN_FILENO);
+
+			exec_or_die(argv);
+		}
+
+		return childproc;
+	}
+
+	/* create a process and redirect it's output to a pipe */
+	inline Proc createRedirProc(const char* const argv[])
+	{
+		fd_t childOut[2];
+		pipe(childOut);
+
+		Proc childproc;
+		childproc.in = STDIN_FILENO;
+		childproc.out = childOut[0];
+
+		childproc.pid = fork();
+		/* close(STDIN_FILENO); flush?*/
+		if(childproc.pid != 0)				/* parent */
+		{
+			close(childOut[1]);
+		}
+		else
+		{
+			dup2(childOut[1], STDOUT_FILENO);
+
+			exec_or_die(argv);
+		}
+
+		return childproc;
+	}
+
+	/* create a process redirecting both in and out */
+	inline Proc createRedirProc(const char* const argv[], const fd_t childIn[2])
+	{
+		fd_t childOut[2];			/* todo: add error #include "processTypes.hpp"*/
+		pipe(childOut);
+
+		Proc childproc;
+		childproc.in = childIn[1];
+		childproc.out = childOut[0];
+
+		childproc.pid = fork();
+		/* close(STDIN_FILENO); flush?*/
+		if(childproc.pid != 0)				/* parent */
+		{
+			close(childOut[1]);
+		}
+		else
+		{
+			close(childIn[1]);
+			dup2(childIn[0], STDIN_FILENO);
+
+			dup2(childOut[1], STDOUT_FILENO);
+
+			exec_or_die(argv);
+		}
+
+		return childproc;
+	}
+}
+
+inline Proc createRedirProcess(const char* const argv[], U32 flags) /* todo rename */
+{
+	fd_t childIn[2];
+	Proc proc;
+
+	if(flags & INPUT)
+	{
+		pipe(childIn);
+		if(flags & OUTPUT)
+			proc = _cppipe::createRedirProc(argv, childIn);
+		else
+			proc = _cppipe::createProc(argv, childIn);
+	}
+	else if(flags & OUTPUT)
+		proc = _cppipe::createRedirProc(argv);
+	else
+		proc = createProcess(argv);
+
+	return proc;
+}
+
+inline Proc createCapProcess(const char* const argv[], fd_t in, fd_t err)
+{
+	fd_t childOut[2];
+	pipe(childOut);
+
+	Proc proc;
+	proc.in = in;
+	proc.out = childOut[0];
+	proc.err = err;
+
+	proc.pid = fork();
+	if(proc.pid == 0)	/* child */
+	{
+		if(in != STDIN_FILENO)
+			dup2(in, STDIN_FILENO);
+
+		dup2(childOut[1], STDOUT_FILENO);
+
+		if(err != STDERR_FILENO)
+			dup2(err, STDERR_FILENO);
+
+		exec_or_die(argv);
+	}
+	else
+	{
+		close(childOut[1]);
+	}
+
+	return proc;
+}
+
+inline Proc createProcess(const char* const argv[], fd_t in, fd_t out, fd_t err)
+{
+	Proc proc;
+	proc.in = in;
+	proc.out = out;
+	proc.err = err;
+
+	proc.pid = fork();
+	if(proc.pid == 0)	/* child */
+	{
+		if(in != STDIN_FILENO)
+			dup2(in, STDIN_FILENO);
+
+		if(out != STDOUT_FILENO)
+			dup2(out, STDOUT_FILENO);
+
+		if(err != STDERR_FILENO)
+			dup2(err, STDERR_FILENO);
+
+		exec_or_die(argv);
+	}
+
+	return proc;
+}
+
+inline void exec_or_die(const char* const argv[])
+{
+	execvp(argv[0], (char* const *)argv);
+
+	std::cerr << "Can't execute: " << argv[0] << ' ' << strerror(errno) << std::endl;
+	_exit(1);		// _exit since we are a child
+}