C help ......please

[Howski]

As I suck at C and linux ...... Can someone help me I've got this code and I need to get the last few errors out before I can start adding stuff..... the first 4 errors are the ones I'm stuck on ...

My code....


/*
A small shell program;
Coursework for UQC109S2 : Networks and operating systems;
Written by Howard Webb (student number 00503227);
This program is free software; you can redistribute it and/or modify
it (if I ever make it avalable!);
Written in Emacs;
Made for, tested and run in Linux
Code moddified from the tutorial found at http://www.hawklord.uklinux.net/system/shell/cs3.htm (Thanks alot!!!);
Prinsibles explained by Nigle Gunton;
Additional code written with the help of (add tut name);
Books used in writting:
C Programming by Tony Royce Published by: Macmillan Press LTD ISBN:0-333-63851-4;
Operating Systems with Linux by John O'Gorman Published by Palgrave Macmillan Ltd ISBN:0333947452 (course text);
*/
#include "def.h"

int main (void)
{
int i;

initcold();

for (;
{
initwarm();

if (getline())
if (i == parse());
execute(i);
}
}
void initcold (void)
{
/*
signal(SIGINT, SIG_IGN);
signal (SIGOUIT, SIG_IGN);
*/
}



void initwarm(void)
{
int i;

backgnd = FALSE;
lineptr = line;
avptr = avline;
infile[0] = '\0';
outfile[0] = '\0';
append = FALSE;

for (i = 0; i<PIPELINE; ++i)
{
cmdlin[i].infd = 0;
cmdlin[i].outfd = 1;
}

for (i = 3; i<MAXOPEN; ++i)
close(i);

printf("Shell: ");
fflush(stdout);
}
int getline (void)
{
int i;

for (i = 0; (line[i] = getchar())!='\n' && i<MAXLINE; ++i);

if (i==MAXLINE)
{
fprintf(stderr, "Command line too long\n");
return(ERROR);
}
line[i+1] = '\0';
return (OKAY);
}
int parse(void)
{
int i;

if (builtin())
return 0;
/* 1 */
command(0);

/* 2 */
if (check("<"))
getname(infile);

/* 3 */
for (i = 1; i<PIPELINE; ++i)
if (check("|"))
command(i);
else
break;

/* 4 */
if (check(">"))
{
if (check(">"))
append = TRUE;

getname(outfile);
}

/* 5 */
if (check("&"))
backgnd = TRUE;

/* 6 */
if (check("\n"))
return(i);
else
{
fprintf(stderr, "Command line syntax error\n");
return (ERROR);
}
}

void command(int i)
{
int j, flag, inword;

for (j = 0; j<MAXARG-1; ++j)
{
while (*lineptr==' ' || *lineptr=='\t')
++lineptr;

cmdlin[i].av[j] = avptr;
cmdlin[i].av[j+1] = NULL;

for (flag = 0; flag==0
{
switch (*lineptr)
{
case '>':
case '<':
case '|':
case '&':
case '\n':
if (inword==FALSE)
cmdlin[i].av[j] = NULL;

*avptr++ = '\0';
return;
case ' ':
case '\t':
inword = FALSE;
*avptr++ = '\0';
flag = 1;
break;
default:
inword = TRUE;
*avptr++ = *lineptr++;
break;
}
}
}
}
void execute(int j)
{
int i, fd, fds[2];

/* 1 */
if (infile[0] !='\0')
cmdlin[0].infd = open(infile, O_RDONLY);

/* 2 */
if (outfile[0] !='\0'){
if (append==FALSE)
cmdlin[j-1].outfd = open(outfile, O_WRONLY | O_CREAT | O_TRUNC, 0666);
else
cmdlin[j-1].outfd = open(outfile, O_WRONLY | O_CREAT | O_APPEND, 0666);
}
/* 3 */
if (backgnd==TRUE)
signal (SIGCHLD, SIG_IGN);
else
signal (SIGCHLD, SIG_DFL);

/* 4 */
for (i = 0; i <j; ++i)
{
/* 5 */
if (i<j-1)
{
pipe (fds);
cmdlin[i].outfd = fds[1];
cmdlin[i+1].infd = fds[0];
}

/* 6 */
forkexec(&cmdlin[i]);

/* 7 */
if ((fd = cmdlin[i].infd)!=0)
close(fd);

if ((fd = cmdlin[i].outfd)!=1)
close(fd);
}

/* 8 */
if (backgnd==FALSE)
while (wait (NULL) != lastpid);
}
int forkexec(struct cmd *ptr)
{
int i, pid;

/* 1 */
if (pid = fork())
{
/* 2 */
if (backgnd==TRUE)
printf("%d\n", pid);
lastpid = pid;
}
else
{
/* 3 */
if (ptr->infd==0 && backgnd==TRUE)
ptr->infd = open("/dev/null", O_RDONLY);

/* 4 */
if (ptr->infd!=0)
{
close(0);
dup(ptr->infd);
}

if (ptr->outfd!=1)
{
close(1);
dup(ptr->outfd);
}

/* 5 */
if (backgnd==FALSE)
{
signal (SIGINT, SIG_DFL);
signal (SIGQUIT, SIG_DFL);
}

/* 6 */
for (i = 3; i<MAXOPEN; ++i)
close(i);

/* 7 */
execvp(ptr->av[0] ptr->av);
exit(1);
}
}
int check(char *ptr)
{
char *tptr;

while (*lineptr== ' ' )
lineptr++;

tptr = lineptr;

while (*ptr!='\0' && *ptr==*tptr)
{
ptr++;
tptr++;
}
if (*ptr!='\0')
return(FALSE);
else
{
lineptr = tptr;
return(TRUE);
}
}
int getname(char *name)
{
int i;

for (i = 0; i<MAXNAME; ++i)
{
switch (*lineptr)
{
case '>':
case '<':
case '|':
case '&':
case ' ':
case '\n':
case '\t':
*name = '\0';
return(-1);

default:
*name++ = *lineptr++;
break;
}
}
*name = '\0';
}
int builtin(void)
{
if (check("exit"))
exit (0);
else if (check("cd"))
return do_cd();
else if (check("pwd"))
return do_pwd();
else
return 0;
}



and def.h


/*
DEf.H to be included in Coursework for UQC109S2 : Network and Operating Systems, with Cousework.c
Code modified form that found at
*/
#include <stdio.h>
#include <limits.h>
#include <signal.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <stdlib.h>
#include <unistd.h>

#define TRUE 1
#define FALSE 0
#define OKAY 1
#define ERROR 0
#define MAXOPEN 16 /* maximum open pipes */
#define MAXLINE 200 /* Maximum length of input line */
#define MAXARG 20 /* Max number of args for each simple command */
#define PIPELINE 5 /* Max number of simple commands in a pipeline */
#define MAXNAME 100 /* Maximum length of i/o redirection filename */

char line[MAXLINE+1]; /* User typed input line */
char *lineptr; /* Pointer to current position in line[] */
char avline[MAXLINE+1]; /* Argv strings taken from line[] */
char *avptr; /* Pointer to current position in avline[] */
char infile[MAXNAME+1]; /* Input redirection filename */
char outfile[MAXNAME+1]; /* Ouput redirection filename */

int backgnd; /* TRUE if & ends pipeline else FALSE */
int lastpid; /* PID of last simple command in pipeline */
int append; /* TRUE for append redirection (») else FALSE */

struct cmd
{
char *av[MAXARG];
int infd;
int outfd;
} cmdlin[PIPELINE]; /* Argvs and fds, one per simple command */
/*
added stuff to stop warnings
*/
void initcold(void);
void initwarm(void);
int getline(void);
int parse(void);
void execute(int j);
int close(int);
int builtin(void);
void command(int i);
int getname(char *name);
int check(char *ptr);
int forkexec(struct cmd *ptr);
int do_cd(void);
void err_sys(const char *, ...);
char path_alloc(int *);


and my version of pwd (untested as of yet!!)

#include "def.h"
int
main(void)
{
char *ptr;
int size;
getcwd(ptr, size);
printf("cwd = %s\n", ptr);
exit(0);
}


Any help would be brill thanx
-How.

[Howski]

here you go errors

cd /coursework/
gcc -Wall -pedantic -ansi Coursework.c
Coursework.c: In function `forkexec':
Coursework.c:215: warning: suggest parentheses around assignment used as truth value
Coursework.c:253: parse error before `ptr'
Coursework.c:256: warning: control reaches end of non-void function
Coursework.c: In function `getname':
Coursework.c:303: warning: control reaches end of non-void function
Coursework.c: In function `builtin':
Coursework.c:311: warning: implicit declaration of function `do_pwd'
Coursework.c: At top level:
Coursework.c:325: conflicting types for `do_cd'
def.h:55: previous declaration of `do_cd'
Coursework.c: In function `do_cd':
Coursework.c:324: parameter name omitted
Coursework.c:326: warning: control reaches end of non-void function

it's the no void function ones I don't get and parentheses around assignment used as truth value
-How.

[Howski]

it's ok I got it now.
-How.