xref: /csrg-svn/bin/sh/error.c (revision 69272)

/*-
 * Copyright (c) 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Kenneth Almquist.
 *
 * %sccs.include.redist.c%
 */

#ifndef lint
static char sccsid[] = "@(#)error.c	8.2 (Berkeley) 05/04/95";
#endif /* not lint */

/*
 * Errors and exceptions.
 */

#include "shell.h"
#include "main.h"
#include "options.h"
#include "output.h"
#include "error.h"
#include "show.h"
#include <signal.h>
#include <unistd.h>
#include <errno.h>


/*
 * Code to handle exceptions in C.
 */

struct jmploc *handler;
int exception;
volatile int suppressint;
volatile int intpending;
char *commandname;


/*
 * Called to raise an exception.  Since C doesn't include exceptions, we
 * just do a longjmp to the exception handler.  The type of exception is
 * stored in the global variable "exception".
 */

void
exraise(e)
	int e;
{
	if (handler == NULL)
		abort();
	exception = e;
	longjmp(handler->loc, 1);
}


/*
 * Called from trap.c when a SIGINT is received.  (If the user specifies
 * that SIGINT is to be trapped or ignored using the trap builtin, then
 * this routine is not called.)  Suppressint is nonzero when interrupts
 * are held using the INTOFF macro.  The call to _exit is necessary because
 * there is a short period after a fork before the signal handlers are
 * set to the appropriate value for the child.  (The test for iflag is
 * just defensive programming.)
 */

void
onint() {
	sigset_t sigset;

	if (suppressint) {
		intpending++;
		return;
	}
	intpending = 0;
	sigemptyset(&sigset);
	sigprocmask(SIG_SETMASK, &sigset, NULL);
	if (rootshell && iflag)
		exraise(EXINT);
	else
		_exit(128 + SIGINT);
}



void
error2(a, b)
	char *a, *b;
	{
	error("%s: %s", a, b);
}


/*
 * Error is called to raise the error exception.  If the first argument
 * is not NULL then error prints an error message using printf style
 * formatting.  It then raises the error exception.
 */

#if __STDC__
void
error(char *msg, ...)
#else
void
error(va_alist)
	va_dcl
#endif
{
#if !__STDC__
	char *msg;
#endif
	va_list ap;
	CLEAR_PENDING_INT;
	INTOFF;

#if __STDC__
	va_start(ap, msg);
#else
	va_start(ap);
	msg = va_arg(ap, char *);
#endif
#ifdef DEBUG
	if (msg)
		TRACE(("error(\"%s\") pid=%d\n", msg, getpid()));
	else
		TRACE(("error(NULL) pid=%d\n", getpid()));
#endif
	if (msg) {
		if (commandname)
			outfmt(&errout, "%s: ", commandname);
		doformat(&errout, msg, ap);
		out2c('\n');
	}
	va_end(ap);
	flushall();
	exraise(EXERROR);
}



/*
 * Table of error messages.
 */

struct errname {
	short errcode;		/* error number */
	short action;		/* operation which encountered the error */
	char *msg;		/* text describing the error */
};


#define ALL (E_OPEN|E_CREAT|E_EXEC)

STATIC const struct errname errormsg[] = {
	{ EINTR,	ALL,	"interrupted" },
	{ EACCES,	ALL,	"permission denied" },
	{ EIO,		ALL,	"I/O error" },
	{ ENOENT,	E_OPEN,	"no such file" },
	{ ENOENT,	E_CREAT,"directory nonexistent" },
	{ ENOENT,	E_EXEC,	"not found" },
	{ ENOTDIR,	E_OPEN,	"no such file" },
	{ ENOTDIR,	E_CREAT,"directory nonexistent" },
	{ ENOTDIR,	E_EXEC,	"not found" },
	{ EISDIR,	ALL,	"is a directory" },
#ifdef notdef
	{ EMFILE,	ALL,	"too many open files" },
#endif
	{ ENFILE,	ALL,	"file table overflow" },
	{ ENOSPC,	ALL,	"file system full" },
#ifdef EDQUOT
	{ EDQUOT,	ALL,	"disk quota exceeded" },
#endif
#ifdef ENOSR
	{ ENOSR,	ALL,	"no streams resources" },
#endif
	{ ENXIO,	ALL,	"no such device or address" },
	{ EROFS,	ALL,	"read-only file system" },
	{ ETXTBSY,	ALL,	"text busy" },
#ifdef SYSV
	{ EAGAIN,	E_EXEC,	"not enough memory" },
#endif
	{ ENOMEM,	ALL,	"not enough memory" },
#ifdef ENOLINK
	{ ENOLINK,	ALL,	"remote access failed" },
#endif
#ifdef EMULTIHOP
	{ EMULTIHOP,	ALL,	"remote access failed" },
#endif
#ifdef ECOMM
	{ ECOMM,	ALL,	"remote access failed" },
#endif
#ifdef ESTALE
	{ ESTALE,	ALL,	"remote access failed" },
#endif
#ifdef ETIMEDOUT
	{ ETIMEDOUT,	ALL,	"remote access failed" },
#endif
#ifdef ELOOP
	{ ELOOP,	ALL,	"symbolic link loop" },
#endif
	{ E2BIG,	E_EXEC,	"argument list too long" },
#ifdef ELIBACC
	{ ELIBACC,	E_EXEC,	"shared library missing" },
#endif
	{ 0,		0,	NULL },
};


/*
 * Return a string describing an error.  The returned string may be a
 * pointer to a static buffer that will be overwritten on the next call.
 * Action describes the operation that got the error.
 */

char *
errmsg(e, action)
	int e;
	int action;
{
	struct errname const *ep;
	static char buf[12];

	for (ep = errormsg ; ep->errcode ; ep++) {
		if (ep->errcode == e && (ep->action & action) != 0)
			return ep->msg;
	}
	fmtstr(buf, sizeof buf, "error %d", e);
	return buf;
}