error.c

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/*-
 * Copyright (c) 1991 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Kenneth Almquist.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
static char sccsid[] = "@(#)error.c     5.1 (Berkeley) 3/7/91";
#endif /* not lint */

/*
 * Errors and exceptions.
 */

#include "shell.h"
#include "main.h"
#include "options.h"
#include "output.h"
#include "error.h"
#include <sys/types.h>
#include <signal.h>
#ifdef __STDC__
#include "stdarg.h"
#else
#include <varargs.h>    
#endif
#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) {
        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() {
        if (suppressint) {
                intpending++;
                return;
        }
        intpending = 0;
#ifdef BSD
        sigsetmask(0);
#endif
        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.
 */

#ifdef __STDC__
void
error(char *msg, ...) {
#else
void
error(va_alist)
        va_dcl
        {
        char *msg;
#endif
        va_list ap;

        CLEAR_PENDING_INT;
        INTOFF;
#ifdef __STDC__
        va_start(ap, msg);
#else
        va_start(ap);
        msg = va_arg(ap, char *);
#endif
#if 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);
}


#ifdef notdef   /* These strange error messages only confuse. -- kjb */
/*
 * 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",
        ENOEXEC, ALL,   "not an executable",
        EISDIR, ALL,    "is a directory",
/*    EMFILE, ALL,      "too many open files", */
        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) {
        const struct errname *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;
}
#endif

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