util.c

/*
** util.c
**
** Made by (Matthieu Lucotte)
** Login   <gounter@users.sourceforge.net>
**
** Started on  Tue Oct  2 20:28:27 2001 Matthieu Lucotte
** Last update Mon Sep  1 23:01:34 2003
*/

#include "zssh.h"


/* shift position i by n chars
 * Ex : str_shift("1234567",2,3) -> "1267"
 *                   |||
 */
void str_shift(char *str, int i, int n)
{
	int j;

	for (j = i; str[j + n]; j++)
		str[j] = str[j + n];
	str[j] = str[j + n];
}


char *str_n_dup(char *str, int n)
{
	char *pt;
	int i;
	int len;

	len = min(strlen(str), n);
	pt = smalloc(len + 1);
	for (i = 0; i < len; i++)
		pt[i] = str[i];
	pt[len] = 0;
	return pt;
}


char *str_cat(char *str1, char *str2)
{
	int i;
	int len1;
	int len2;
	char *str_res;

	len1 = strlen(str1);
	len2 = strlen(str2);
	if ((str_res = smalloc(len1 + len2 + 1)) == 0)
		return 0;
	for (i = 0; i < len1; i++)
		str_res[i] = str1[i];
	for (i = 0; i <= len2; i++)
		str_res[len1 + i] = str2[i];
	return str_res;
}


void str_sub_repl(char **str, int sub_beg, int sub_len, char *sub_repl)
{
	char *s1;
	char *s2;

	s1 = s2 = str_n_dup(*str, sub_beg);
	s1 = str_cat(s1, sub_repl);
	free(s2);
	s2 = s1;
	s1 = str_cat(s1, *str + sub_beg + sub_len);
	free(s2);
	free(*str);
	*str = s1;
}



void *smalloc(unsigned int n)
{
	void         *pt;

	if ((pt = malloc(n)) != 0)
		return pt;
	error(0, "malloc");
	exit(1);
}


/*int	sfork() */
/*{ */
/*   int  pid; */
/*    */
/*   pid = fork(); */
/*   if (pid == -1) */
/*      error(0,"fork"); */
/*   return (pid); */
/*} */

/* sfork(): Exits if unable to fork
 * if pid_child is non zero, also avoids race condition that would occur
 * if the child's pid must be known by the parent *before* the child dies.
 */
int sfork(volatile sig_atomic_t *pid_child)
{
	sigset_t mask;
	sigset_t old_mask;
	int pid;

	sigprocmask(SIG_SETMASK, 0, &old_mask); /* save mask */
	sigprocmask(SIG_SETMASK, 0, &mask);
	sigaddset(&mask, SIGCHLD);
	sigprocmask(SIG_SETMASK, &mask, 0);     /* block SIGCHLD */
	pid = fork();
	if (pid == -1)
		error(0, "fork");
	if (pid)        /* parent process */
		if (pid_child)
			*pid_child = pid;
	sigprocmask(SIG_SETMASK, &old_mask, 0); /* restore old mask */
	return pid;
}

void copy_rz_stream(int read_fd, int write_fd) {
	ssize_t cr, cw;
	char buf[ZSSH_IO_BUFSIZ];
	while (gl_child_rz) {
		cr = read(read_fd, buf, sizeof(buf)); /* read from ssh pty */
		if (cr <= 0)
			break;
		cw = write(write_fd, buf, cr); /* write to hook process */
		if (cw < 0) {
			break;
		}
		if (cr != cw) {
			fprintf(stderr, "error: partial write, %zd != %zd\n", cr, cw);
		}
	}
}