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#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <io.h>
#include <fcntl.h>
#include <process.h>
#include <errno.h>
#include <sys\stat.h>
char err_buf[128];
void msg_error(char *msg)
{
strcpy(err_buf, msg);
}
static char *shell = NULL, *shell_switch = NULL;
static void discover_shell(void)
{
#ifdef SH_SHELL /* maybe some day ... */
shell_switch = "-c";
if ( (shell = getenv("SHELL")) != NULL ) return;
#endif
shell_switch = "/c";
if ( (shell = getenv("COMSPEC")) != NULL ) return;
shell = "command.com"; /* absolute last resort! */
}
/* ///////////////////////////////////////////////////////////////////
// Function: static int parse_command_line( int *argc, char ***argv,
// char **fname,
// char *command_line );
// Descript: parse command_line
//
// Returns: the handles to redirect
//
// Caveat: requires spaces to separate each argument
// ie., args>filename will NOT work
///////////////////////////////////////////////////////////////////// */
#define DIRECT_SPAWN 0x1000 /* some arbitrary number */
static int
parse_command_line( int *argc, char ***argv, char **fname, char *command_line )
{
int count, handles = 0;
char *pt;
discover_shell(); /* find which shell to use */
while ( (*command_line != '\0') && (*command_line == ' '))
command_line++; /* start on 1st non-space */
if ( *command_line == '!' ) {
handles = DIRECT_SPAWN;
command_line++; /* advance past '!' */
while ((*command_line != '\0') && (*command_line == ' '))
command_line++; /* start on next non-space */
}
pt = command_line;
count = 0;
while ( *pt != '\0' ) {
count++; /* this is an argument */
while ((*pt != '\0') && (*pt != ' '))
{
if ( *pt == '|' ) /* cannot spawn directly */
handles = 0; /* need shell for pipes */
pt++; /* advance until a space */
}
while ( *pt == ' ' )
pt++; /* advance until a non-space */
}
*argv = (char **) malloc( (count+3) * sizeof(char *) );
if ( *argv == NULL )
return 0; /* malloc error */
*argc = 0;
if ( !(handles & DIRECT_SPAWN) ) {
(*argv)[ *argc ] = shell;
(*argc)++;
if ( count > 0 ) {
(*argv)[ *argc ] = shell_switch;
(*argc)++;
}
count += (*argc);
}
pt = command_line;
while ((*argc < count) && (*pt != '\0')) {
(*argv)[ *argc ] = pt;
(*argc)++;
while ( *pt != '\0' && *pt != ' ' )
pt++; /* advance until a space */
if ( *pt != '\0' )
*(pt++) = '\0'; /* parse argument here */
while ( *pt == ' ')
pt++; /* advance until a non-space */
}
(*argv) [ *argc ] = (char *) NULL; /* NULL terminated list */
/* now examine the arguments for '>' redirect */
for ( count = 0; count < *argc; count++ ) {
for ( pt = (*argv)[count]; *pt && *pt != '>'; pt++ )
/* find '>' char */;
if ( *pt == '>' ) {
if ( pt == (*argv)[count] ) {
handles |= 0x01;
} else {
switch ( *(--pt) ) {
case '1':
handles |= 0x01;
break;
case '2':
handles |= 0x02;
break;
case '&':
handles |= 0x03;
break;
}
}
(*argv)[count] = NULL; /* remove from the list */
count++; /* file name follows '>' */
if ( (*argv)[count] != NULL )
*fname = (*argv)[count];
}
}
if ((*fname == NULL) || (**fname == '\0' ))
handles = 0x00; /* don't redirect if there is no name */
return handles;
}
/* ///////////////////////////////////////////////////////////////////
// Function: int sys_System(char *command_line);
//
// Descript: shell wrapper that understands some common redirection syntax
// command args > filename ; stdout
// command args 1> filename ; stdout
// command args 2> filename ; stderr
// command args &> filename ; stdout+stderr
// command args > filename 2>&1 ; stdout+stderr
//
// additionally, if command is prefixed by a '!', then the command is
// spawned directly without invoking the shell
//
// Returns: returns error codes as per spawn*()
//
// Caveat: requires spaces to separate each argument
// ie., command args>filename will NOT work
///////////////////////////////////////////////////////////////////// */
static int execute_the_command (char **, int, char *);
int sys_System(char *command_line)
{
int ret = -1, handles, argc = 0;
char *fname = NULL, **argv = NULL;
handles = parse_command_line( &argc, &argv, &fname, command_line );
if (argc)
{
ret = execute_the_command (argv, handles, fname);
}
return ret;
}
static int execute_the_command (char **argv, int handles, char *file)
{
int ret = 0;
int fd1 = -1, fd2 = -1;
int fd_err = -1, fd_out = -1;
if (handles & 1)
{
/* save stdout file handle */
fd1 = dup (fileno (stdout));
if (fd1 == -1)
{
msg_error ("Unable to dup stdout");
return -1;
}
fd_out = open (file,
O_CREAT | O_TRUNC | O_TEXT | O_WRONLY | O_APPEND,
S_IREAD | S_IWRITE);
if ((fd_out == -1) || (-1 == dup2 (fd_out, fileno (stdout))))
{
msg_error ("Unable to redirect stdout!");
ret = -1;
}
}
if (handles & 0x2) /* stderr */
{
/* save stderr file handle */
fd2 = dup (fileno (stderr));
if (fd2 == -1)
{
msg_error ("Unable to dup stderr");
return -1;
}
if (fd_out == -1)
{
fd_err = open (file,
O_CREAT | O_TRUNC | O_TEXT | O_RDWR | O_APPEND,
S_IREAD | S_IWRITE);
}
else fd_err = fd_out;
if ((fd_err == -1) || (-1 == dup2 (fd_err, fileno (stderr))))
{
msg_error ("Unable to redirect stderr!");
ret = -1;
}
}
if (fd_out != -1) close (fd_out);
if ((fd_err != -1) && (fd_err != fd_out)) close (fd_err);
if (ret == 0)
{
ret = spawnvp(P_WAIT, argv[0], (void *) argv);
if (-1 == ret )
{
switch(errno)
{
case ENOENT:
if (handles & DIRECT_SPAWN ) msg_error("Command not found.");
else msg_error("Shell not found.");
break;
case ENOMEM:
msg_error("Insufficient Memory.");
break;
default:
msg_error("Unknown Error.");
}
}
}
if (fd1 != -1)
{
if (-1 == dup2 (fd1, fileno (stdout)))
{
msg_error ("Unable to reattach stdout");
}
close (fd1);
}
if (fd2 != -1)
{
if (-1 == dup2 (fd2, fileno (stderr)))
{
msg_error ("Unable to reattach stderr");
}
close (fd2);
}
return ret;
}
int main(int argc, char **argv)
{
char *command_line, *p;
int i, j;
FILE *f;
int ret;
err_buf[0] = 0;
for(i = j = 1; i < argc; i++)
j += strlen(argv[i]) + 1;
if (NULL == (p = command_line = malloc(j + 1)))
{
msg_error("Malloc error");
ret = -1;
}
else
{
for(i = 1; i < argc; i++)
{
strcpy(p, argv[i]);
p += strlen(argv[i]);
*p++ = ' ';
}
*p = 0;
ret = sys_System(command_line);
free(command_line);
}
f = fopen("jedshell.tmp", "w");
if (f == NULL)
{
/* I realize that this does nothing... */
msg_error ("Unable to open tmp file.");
return -1;
}
fprintf(f, "%d\n%s", ret, err_buf);
fclose(f);
return 0;
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.