/* bcc.c - driver for Bruce's C compiler (bcc) and for CvW's C compiler */

/* Copyright (C) 1992 Bruce Evans */

#define _POSIX_SOURCE 1

#include <sys/types.h>
#include <sys/stat.h>
#ifndef MSDOS
#include <sys/wait.h>
#include <unistd.h>
#endif
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>

#define FALSE	0
#define FORWARD	static
#define NUL_PTR	((void*)0)
#define PRIVATE	static
#define PUBLIC
#define TRUE	1

#ifdef __STDC__
#define P(x)	x
#else
#define P(x)	()
#endif

#ifdef MSDOS
#define LOCALPREFIX	"/linux86"
#define EXESUF          ".exe"
#define	R_OK	4		/* Test for read permission.  */
#define	W_OK	2		/* Test for write permission.  */
#define	X_OK	1		/* Test for execute permission.  */
#define	F_OK	0		/* Test for existence.  */
#else
#define EXESUF
#endif

#define BAS86
#define BCC86

#define AS			"as86" EXESUF
#define CC1			"bcc-cc1" EXESUF
#define CC1_MINUS_O_BROKEN	FALSE
#define CPP			"bcc-cc1" EXESUF
#define CPPFLAGS		"-E"
#define CRT0			"crt0.o"
#define GCC			"gcc"
#define LD			"ld86" EXESUF
#define UNPROTO 		"unproto" EXESUF

#ifdef MSDOS
#define STANDARD_CRT0_0_PREFIX	"~/lib/"
#define STANDARD_CRT0_3_PREFIX	"~/lib/i386/"
#define STANDARD_EXEC_PREFIX	"~/lib/"
#define STANDARD_EXEC_PREFIX_2	"~/bin/"
#define DEFAULT_INCLUDE 	"-I~/include"
#define DEFAULT_LIBDIR0		"-L~/lib/"
#define DEFAULT_LIBDIR3		"-L~/lib/i386/"
#else
#define STANDARD_CRT0_0_PREFIX	"~/lib/bcc/i86/"
#define STANDARD_CRT0_3_PREFIX	"~/lib/bcc/i386/"
#define STANDARD_EXEC_PREFIX	"~/lib/bcc/"
#define STANDARD_EXEC_PREFIX_2	"/usr/bin/"
#define DEFAULT_INCLUDE         "-I~/include"
#define DEFAULT_LIBDIR0         "-L~/lib/bcc/i86/"
#define DEFAULT_LIBDIR3         "-L~/lib/bcc/i386/"
#endif

#ifdef CCC
#undef BCC86
#undef CC1
#define CC1	"c386"
#undef CC1_MINUS_O_BROKEN
#define CC1_MINUS_O_BROKEN	TRUE
#undef STANDARD_CRT0_0_PREFIX
#undef STANDARD_CRT0_3_PREFIX
#define STANDARD_CRT0_PREFIX	"~/lib/i386/"
#endif /* CCC */

#ifdef MC6809
#undef BAS86
#undef BCC86
#undef CRT0
#undef GCC
#undef STANDARD_CRT0_0_PREFIX
#undef STANDARD_CRT0_3_PREFIX
#undef STANDARD_EXEC_PREFIX
#define STANDARD_EXEC_PREFIX	"~/lib/bcc/m09/"
#endif /* MC6809 */

#define ALLOC_UNIT	16	/* allocation unit for arg arrays */
#define DIRCHAR	'/'
#define START_ARGS	4	/* number of reserved args */

typedef unsigned char bool_T;	/* boolean: TRUE if nonzero */

struct arg_s
{
    char *prog;
    bool_T minus_O_broken;
    int argc;
    char **argv;
    unsigned nr_allocated;
};

struct prefix_s
{
    char *name;
    struct prefix_s *next;
};

PRIVATE struct arg_s asargs = { AS, };
PRIVATE struct arg_s ccargs = { CC1, CC1_MINUS_O_BROKEN, };
PRIVATE struct arg_s cppargs = { CPP, };
PRIVATE struct arg_s unprotoargs = { UNPROTO, TRUE };
#ifdef STANDARD_CRT0_PREFIX
PRIVATE struct prefix_s crt0_prefix = { STANDARD_CRT0_PREFIX, };
#endif
#ifdef STANDARD_CRT0_0_PREFIX
PRIVATE struct prefix_s crt0_0_prefix = { STANDARD_CRT0_0_PREFIX, };
#endif
#ifdef STANDARD_CRT0_3_PREFIX
PRIVATE struct prefix_s crt0_3_prefix = { STANDARD_CRT0_3_PREFIX, };
#endif
PRIVATE struct prefix_s exec_prefix;
PRIVATE struct arg_s ldargs = { LD, };
#ifdef BAS86
PRIVATE struct arg_s ldrargs = { LD, };
#endif
PRIVATE char *progname;
PRIVATE bool_T runerror;	/* = FALSE */
PRIVATE struct arg_s tmpargs;	/* = empty */
PRIVATE char *tmpdir;
PRIVATE unsigned verbosity;	/* = 0 */

PRIVATE char * localprefix = LOCALPREFIX;

#ifdef REDECLARE_STDC_FUNCTIONS
void exit P((int status));
char *getenv P((const char *name));
void *malloc P((size_t size));
void *realloc P((void *ptr, size_t size));
void (*signal P((int sig, void (*func) P((int sig))))) P((int sig));
char *strcpy P((char *dest, const char *src));
size_t strlen P((const char *s));
char *strrchr P((const char *s, int c));
#endif

#ifdef REDECLARE_POSIX_FUNCTIONS
int access P((const char *path, int amode));
int execv P((const char *path, char * const *argv));
pid_t fork P((void));
pid_t getpid P((void));
int unlink P((const char *path));
pid_t wait P((int *status));
ssize_t write P((int fd, const void *buf, size_t nbytes));
#endif

int main P((int argc, char **argv));

FORWARD void addarg P((struct arg_s *argp, char *arg));
FORWARD void addprefix P((struct prefix_s *prefix, char *name));
FORWARD char *expand_tilde P((char * str, int canfree));
FORWARD void fatal P((char *message));
FORWARD char *fixpath P((char *path, struct prefix_s *prefix, int mode));
FORWARD void killtemps P((void));
FORWARD void *my_malloc P((unsigned size, char *where));
FORWARD char *my_mktemp P((void));
FORWARD void my_unlink P((char *name));
FORWARD void outofmemory P((char *where));
FORWARD int run P((char *in_name, char *out_name, struct arg_s *argp));
#ifdef MSDOS
FORWARD void reset_localprefix P((void));
#endif
FORWARD void set_trap P((void));
FORWARD void show_who P((char *message));
FORWARD void startarg P((struct arg_s *argp));
FORWARD char *stralloc P((char *s));
FORWARD char *stralloc2 P((char *s1, char *s2));
FORWARD void trap P((int signum));
FORWARD void unsupported P((char *option, char *message));
FORWARD void writen P((void));
FORWARD void writes P((char *s));
FORWARD void writesn P((char *s));
FORWARD void linux_patch P((char * fname));

PUBLIC int main(argc, argv)
int argc;
char **argv;
{
    char *arg;
    int add_default_inc = 1;
    int add_default_lib = 1;
    int argcount = argc;
    bool_T *argdone = my_malloc((unsigned) argc * sizeof *argdone, "argdone");
    bool_T as_only = FALSE;
    char *basename;
#ifdef BCC86
#ifdef DEFARCH
    bool_T bits32 = (DEFARCH != 0);
#else
    bool_T bits32 = sizeof (char *) >= 4;
#endif
    char *bits_arg;
#endif
    bool_T cc_only = FALSE;
    bool_T ansi_pass = FALSE;
#ifdef CCC
    bool_T cpp_pass = TRUE;
#else
    bool_T cpp_pass = FALSE;
#endif
#ifdef BCC86
    char *crt0;
#endif
    char *libc = "-lc";
    bool_T debug = FALSE;
    bool_T echo = FALSE;
    unsigned errcount = 0;
    char ext;
    char *f_out = NUL_PTR;
    bool_T float_emulation = FALSE;
#ifdef BAS86
    bool_T gnu_objects = FALSE;
#endif
    bool_T aswarn = FALSE;
    char *in_name;
    int length;
    unsigned ncisfiles = 0;
    unsigned nifiles = 0;
    unsigned npass_specs;
    bool_T optimize = FALSE;
    char *out_name;
    bool_T profile = FALSE;
    bool_T prep_only = FALSE;
    bool_T prep_line_numbers = FALSE;
    int status;
    char *temp;
    bool_T patch_exe = FALSE;

    progname = argv[0];
    addarg(&cppargs, CPPFLAGS);
#ifdef CCC
    addarg(&asargs, "-j");
#endif
    addarg(&asargs, "-u");
#ifdef BAS86
    addarg(&ldrargs, "-r");
    addarg(&ldrargs, "-N");	/* GCC uses native objects */
    				/* GCC also uses 386 how to add -3 too ? */
#endif

#ifdef MSDOS
    reset_localprefix();
#endif
    /* Pass 1 over argv to gather compile options. */
    for (; --argc != 0;)
    {
	arg = *++argv;
	*++argdone = TRUE;
	if (arg[0] == '-' && arg[1] != 0 && arg[2] == 0)
	    switch (arg[1])
	    {
#ifdef BCC86
	    case '0':
		bits32 = FALSE;
		break;
	    case '3':
		bits32 = TRUE;
		break;
#endif
	    case 'E':
		prep_only = prep_line_numbers = cpp_pass = TRUE;
		break;
#ifdef BAS86
	    case 'G':
		gnu_objects = TRUE;
		add_default_lib = 0;
		break;
#endif
	    case 'P':
		prep_only = cpp_pass = TRUE;
		prep_line_numbers = FALSE;
		break;
	    case 'O':
		optimize = TRUE;	/* unsupported( arg, "optimize" ); */
		break;
	    case 'S':
		cc_only = TRUE;
#ifndef CCC
		addarg(&ccargs, "-t");
#endif
		break;
	    case 'V':
		echo = TRUE;
		break;
	    case 'c':
		as_only = TRUE;
		break;
	    case 'e':
		cpp_pass = TRUE;
		break;
	    case 'f':
		float_emulation = TRUE;
		++errcount;
		unsupported(arg, "float emulation");
		break;
	    case 'g':
		debug = TRUE;	/* unsupported( arg, "debug" ); */
		break;
	    case 'o':
		if (argc <= 1)
		{
		    ++errcount;
		    show_who("output file missing after -o\n");
		}
		else
		{
		    argc--;
		    if (f_out != NUL_PTR)
			show_who("more than one output file\n");
		    f_out = *++argv;
		    *++argdone = TRUE;
		}
		break;
	    case 'p':
		profile = TRUE;
		++errcount;
		unsupported(arg, "profile");
		break;
	    case 'v':
		++verbosity;
		break;
	    case 'w':
		aswarn=FALSE;
		break;
	    case 'W':
		++aswarn;
		break;
	    case 'I':
		add_default_inc = 0;
		break;
	    case 'L':
		add_default_lib = 0;
		break;
	    default:
		*argdone = FALSE;
		break;
	    }
	else if (arg[0] == '-')
	    switch (arg[1])
	    {
	    case 'a':
	      if (!strcmp(arg, "-ansi"))
	      {
		ansi_pass=TRUE;
		cpp_pass=TRUE;
#ifndef CCC
		/* NOTE I'm setting this to zero, this isn't a _real_ STDC */
		addarg(&ccargs, "-D__STDC__=0");
#endif
		addarg(&cppargs, "-D__STDC__=0");
	      }
	      break;
	    case 'A':
		addarg(&asargs, arg + 2);
		break;
	    case 'B':
		addprefix(&exec_prefix, arg + 2);
		break;
	    case 'C':
		addarg(&ccargs, arg + 2);
		break;
	    case 'D':
	    case 'I':
	    case 'U':
#ifndef CCC
		addarg(&ccargs, arg);
#endif
		addarg(&cppargs, arg);
		break;
	    case 'X':
		addarg(&ldargs, arg + 2);
		break;
	    case 'L':
		addarg(&ldargs, arg);
		break;
	    case 'M':
	        switch(arg[2])
		{
		case 'd': /* DOS compile */
#ifndef CCC
		   addarg(&ccargs, "-D__MSDOS__");
#endif
		   addarg(&cppargs, "-D__MSDOS__");
		   addarg(&ldargs, "-d");
		   addarg(&ldargs, "-s");
		   addarg(&ldargs, "-T100");
		   libc= "-ldos";
		   break;
		case 'f': /* Caller saves+ax is first arg */
		   libc= "-lc_f";
		   addarg(&ccargs, "-f");
		   addarg(&ccargs, "-c");
		   break;
		case 's': /* Standalone executable */
#ifndef CCC
		   addarg(&ccargs, "-D__STANDALONE__");
#endif
		   addarg(&cppargs, "-D__STANDALONE__");
		   addarg(&ldargs, "-s");
		   libc= "-lc_s";
		   break;
		}
		break;
	    case 'P':
		addarg(&cppargs, arg + 2);
		break;
	    case 'Q':
		addarg(&ccargs, arg);
		break;
	    case 'T':
		tmpdir = arg + 2;
		break;
	    case 't':
		++errcount;
		unsupported(arg, "pass number");
		break;
	    default:
		*argdone = FALSE;
		break;
	    }
	else
	{
	    ++nifiles;
	    *argdone = FALSE;
	    length = strlen(arg);
	    if (length >= 2 && arg[length - 2] == '.'
		&& ((ext = arg[length - 1]) == 'c' || ext == 'i' || ext == 'S'
		    || ext == 's'))
		++ncisfiles;
	}
    }
    npass_specs = prep_only + cc_only + as_only;
    if (npass_specs != 0)
    {
	if (npass_specs > 1)
	{
	    ++errcount;
	    show_who("more than 1 option from -E -P -S -c\n");
	}
	if (f_out != NUL_PTR && ncisfiles > 1)
	{
	    ++errcount;
	    show_who("cannot have more than 1 input with non-linked output\n");
	}
    }
    if (nifiles == 0)
    {
	++errcount;
	show_who("no input files\n");
    }
    if (errcount != 0)
	exit(1);

    if( !aswarn )
       addarg(&asargs, "-w");
    if( patch_exe )
       addarg(&ldargs, "-s");
#ifdef BCC86
    else if( !bits32 )
       addarg(&ldargs, "-i");
#endif
    if (verbosity > 2)
    {
       show_who("localprefix set to ");
       writesn(localprefix);
    }
    if ((temp = getenv("BCC_EXEC_PREFIX")) != NUL_PTR)
	addprefix(&exec_prefix, temp);
    if( add_default_inc )
    {
#ifndef CCC
       addarg(&ccargs, DEFAULT_INCLUDE);
#endif
       addarg(&cppargs, DEFAULT_INCLUDE);
    }
    if( add_default_lib )
    {
#ifdef BCC86
#ifdef DEFAULT_LIBDIR3
        if( bits32 )
	    addarg(&ldargs, DEFAULT_LIBDIR3);
        else
#endif
#endif
	    addarg(&ldargs, DEFAULT_LIBDIR0);
    }
    addprefix(&exec_prefix, STANDARD_EXEC_PREFIX);
    addprefix(&exec_prefix, STANDARD_EXEC_PREFIX_2);
    cppargs.prog = fixpath(cppargs.prog, &exec_prefix, X_OK);
    ccargs.prog = fixpath(ccargs.prog, &exec_prefix, X_OK);
    asargs.prog = fixpath(asargs.prog, &exec_prefix, X_OK);
    ldargs.prog = fixpath(ldargs.prog, &exec_prefix, X_OK);
#ifdef BAS86
    ldrargs.prog = fixpath(ldrargs.prog, &exec_prefix, X_OK);
#endif
    unprotoargs.prog=fixpath(unprotoargs.prog, &exec_prefix, X_OK);
    if (tmpdir == NUL_PTR && (tmpdir = getenv("TMPDIR")) == NUL_PTR)
#ifdef MSDOS
	tmpdir = ".";
#else
	tmpdir = "/tmp";
#endif

    if (prep_only && !prep_line_numbers)
	addarg(&cppargs, "-P");
#ifdef BCC86
#ifdef STANDARD_CRT0_3_PREFIX
    if (bits32)
    {
	bits_arg = "-3";
	crt0 = fixpath(CRT0, &crt0_3_prefix, R_OK);
    }
    else
#endif
    {
	bits_arg = "-0";
	crt0 = fixpath(CRT0, &crt0_0_prefix, R_OK);
    }
    addarg(&ccargs, bits_arg);
    addarg(&cppargs, bits_arg);
    addarg(&asargs, bits_arg);
#ifdef BAS86
    if (!gnu_objects)
    {
	addarg(&ldargs, bits_arg);
	addarg(&ldrargs, bits_arg);
	/* addarg(&ldargs, crt0);*/
	addarg(&ldargs, "-C0");
    }
#endif /* BAS86 */
#endif /* BCC86 */
#if defined(BAS86) && !defined(BCC86)
    if (!gnu_objects)
	addarg(&ldargs, fixpath(CRT0, &crt0_prefix, R_OK));
#endif
    set_trap();

    /* Pass 2 over argv to compile and assemble .c, .i, .S and .s files and
     * gather arguments for linker.
     */
    for (argv -= (argc = argcount) - 1, argdone -= argcount - 1; --argc != 0;)
    {
	arg = *++argv;
	if (!*++argdone)
	{
	    length = strlen(arg);
	    if (length >= 2 && arg[length - 2] == '.'
		&& ((ext = arg[length - 1]) == 'c' || ext == 'i' || ext == 'S'
		    || ext == 's'))
	    {
		if (echo || verbosity != 0)
		{
		    writes(arg);
		    writesn(":");
		}
		if ((basename = strrchr(arg, DIRCHAR)) == NUL_PTR)
		    basename = arg;
		else
		    ++basename;
		in_name = arg;
		if (ext == 'c')
		{
		    if (cpp_pass)
		    {
			if (prep_only && !ansi_pass)
			    out_name = f_out;
			else
			    out_name = my_mktemp();
			if (run(in_name, out_name, &cppargs) != 0)
			    continue;
			in_name = out_name;
		        if (ansi_pass)
		        {
			    if (prep_only)
			        out_name = f_out;
			    else
			        out_name = my_mktemp();

			    if (run(in_name, out_name, &unprotoargs) != 0)
			       continue;
			    in_name=out_name;
		        }
		    }
		    ext = 'i';
		}
		if (ext == 'i')
		{
		    if (prep_only)
			continue;
		    if (cc_only)
		    {
			if (f_out != NUL_PTR)
			    out_name = f_out;
			else
			{
			    out_name = stralloc(basename);
			    out_name[strlen(out_name) - 1] = 's';
			}
		    }
		    else
			out_name = my_mktemp();
		    if (run(in_name, out_name, &ccargs) != 0)
			continue;
		    in_name = out_name;
		    ext = 's';
		}
		if (ext == 'S')
		{
		    if (prep_only)
			out_name = f_out;
		    else if (cc_only)
		    {
			if (f_out != NUL_PTR)
			    out_name = f_out;
			else
			{
			    out_name = stralloc(basename);
			    out_name[strlen(out_name) - 1] = 's';
			}
		    }
		    else
			out_name = my_mktemp();
		    if (run(in_name, out_name, &cppargs) != 0)
			continue;
		    in_name = out_name;
		    ext = 's';
		}
		if (ext == 's')
		{
		    if (prep_only || cc_only)
			continue;
		    out_name = stralloc(basename);
		    out_name[strlen(out_name) - 1] = 'o';
		    if (as_only)
		    {
			if (f_out != NUL_PTR)
			    out_name = f_out;
			else
			{
			    out_name = stralloc(basename);
			    out_name[strlen(out_name) - 1] = 'o';
			}
		    }
		    else
			out_name = my_mktemp();
		    addarg(&asargs, "-n");
		    arg[length - 1] = 's';
		    addarg(&asargs, arg);
#ifdef BAS86
		    if (gnu_objects)
		    {
			char *tmp_out_name;

			tmp_out_name = my_mktemp();
			status = run(in_name, tmp_out_name, &asargs);
			asargs.argc -= 2;
			if (status != 0)
			    continue;
			if (run(tmp_out_name, out_name, &ldrargs) != 0)
			    continue;
		    }
		    else
#endif
		    {
			status = run(in_name, out_name, &asargs);
			asargs.argc -= 2;
			if (status != 0)
			    continue;
		    }
		    ext = 'o';
		    in_name = out_name;
		}
		if (ext == 'o')
		{
		    if (prep_only || cc_only || as_only)
			continue;
		    addarg(&ldargs, in_name);
		}
	    }
	    else
		addarg(&ldargs, arg);
	}
    }

    if (!prep_only && !cc_only && !as_only && !runerror)
    {
        int link_st;

	if (f_out == NUL_PTR)
	    f_out = "a.out";
#ifdef BAS86
	if (gnu_objects)
	{
	    /* Remove -i and -i-. */
	    for (argc = ldargs.argc - 1; argc >= START_ARGS; --argc)
	    {
		arg = ldargs.argv[argc];
		if (arg[0] == '-' && arg[1] == 'i'
		    && (arg[2] == 0 || (arg[2] == '-' && arg[3] == 0)))
		{
		    --ldargs.argc;
		    memmove(ldargs.argv + argc, ldargs.argv + argc + 1,
			    (ldargs.argc - argc) * sizeof ldargs.argv[0]);
		    ldargs.argv[ldargs.argc] = NUL_PTR;
		}
	    }

	    ldargs.prog = fixpath(GCC, &exec_prefix, X_OK);
	    link_st = run((char *) NUL_PTR, f_out, &ldargs);
	}
	else
#endif
	{
	    addarg(&ldargs, libc);
	    link_st = run((char *) NUL_PTR, f_out, &ldargs);
	}
	if( patch_exe && link_st == 0 )
	   linux_patch(f_out);
    }
    if( runerror && f_out != NUL_PTR )
       my_unlink(f_out);
    killtemps();
    return runerror ? 1 : 0;
}

PRIVATE void linux_patch(fname)
char * fname;
{
/* OMAGIC */

#define AOUT_MAG	0x640107L
#define ELKS_MAG1	0x1010
#define ELKS_MAG2	0x1011	/* -z */
#define ELKS_MAG3	0x1020	/* -i */
#define ELKS_MAG4	0x1021	/* -i -z */

static struct	ELKS_exec {	/* ELKS a.out header */
  long 		a_magic;	/* magic number */
  long		a_hdrlen;	/* length, etc of header */
  long		a_text;		/* size of text segement in bytes */
  long		a_data;		/* size of data segment in bytes */
  long		a_bss;		/* size of bss segment in bytes */
  long		a_entry;	/* entry point */
  long		a_total;	/* total memory allocated */
  long		a_syms;		/* size of symbol table */
}  instr;


static struct  aout_exec {
  unsigned long a_info;	/* Use macros N_MAGIC, etc for access */
  unsigned a_text;	/* length of text, in bytes */
  unsigned a_data;	/* length of data, in bytes */
  unsigned a_bss;	/* length of uninitialized data area, in bytes */
  unsigned a_syms;	/* length of symbol table data in file, in bytes */
  unsigned a_entry;	/* start address */
  unsigned a_trsize;	/* length of relocation info for text, in bytes */
  unsigned a_drsize;	/* length of relocation info for data, in bytes */
} outstr;

   int fd;

   fd = open(fname, O_RDWR);
   if( fd<0 ) return;

   if( read(fd, &instr, sizeof(instr)) != sizeof(instr) )
   {
      writesn("Cannot re-read executable header");
      return;
   }

   if( instr.a_hdrlen != 0x20 || (instr.a_magic & 0xFFFF) != 0x0301 )
   {
      writesn("Executable cannot be converted to OMAGIC");
      return;
   }

   switch((int)(instr.a_magic >> 16))
   {
   case ELKS_MAG1:
      outstr.a_info = AOUT_MAG;
      break;
   case ELKS_MAG2:
      writesn("Executable cannot be converted to OMAGIC");
      return;
   case ELKS_MAG3:
   case ELKS_MAG4:
      writesn("Executable file is split I/D, data overlaps text");
      return;
   default:
      writesn("Executable cannot be converted to OMAGIC");
      return;
   }

   if( instr.a_syms != 0 )
      writesn("Warning: executable file isn't stripped");

   outstr.a_text = instr.a_text;
   outstr.a_data = instr.a_data;
   outstr.a_bss  = instr.a_bss;
   outstr.a_entry= instr.a_entry;

   lseek(fd, 0L, 0);

   if( write(fd, &outstr, sizeof(outstr)) != sizeof(outstr) )
   {
      writesn("Cannot re-write executable header");
      return;
   }

   close(fd);
}

#ifdef MSDOS
PRIVATE void reset_localprefix()
{
   char *ptr, *temp;

   temp = stralloc(progname);
   if( (ptr = strrchr(temp, '\\')) != 0
         && temp<ptr-4 && strncmp(ptr-4, "\\BIN", 4) == 0 )
   {
      ptr[-4] = 0;
      localprefix = temp;
      if (verbosity > 2)
      {
         show_who("localprefix is now ");
	 writesn(localprefix);
      }
   }
   else
      free(temp);
}
#endif

PRIVATE char * expand_tilde(str, canfree)
char * str;
int canfree;
{
   char * newstr;
   char * ptr = strchr(str, '~');
   if( ptr == 0 ) return str;

   newstr = my_malloc(strlen(str)+strlen(localprefix), "expand tilde");
   if( ptr!=str ) memcpy(newstr, str, ptr-str);
   strcpy(newstr+(ptr-str), localprefix);
   strcat(newstr, ptr+1);
   if( canfree ) free(str);
   return newstr;
}

PRIVATE void addarg(argp, arg)
register struct arg_s *argp;
char *arg;
{
    int new_argc;
    char **new_argv;

    if (argp->nr_allocated == 0)
	startarg(argp);
    new_argc = argp->argc + 1;
    if (new_argc >= argp->nr_allocated)
    {
	argp->nr_allocated += ALLOC_UNIT;
	new_argv = realloc(argp->argv, argp->nr_allocated * sizeof *argp->argv);
	if (new_argv == NUL_PTR)
	    outofmemory("addarg");
	argp->argv = new_argv;
    }
    argp->argv[argp->argc] = expand_tilde(arg, 0);
    argp->argv[argp->argc = new_argc] = NUL_PTR;
}

PRIVATE void addprefix(prefix, name)
struct prefix_s *prefix;
char *name;
{
    struct prefix_s *new_prefix;

    if (prefix->name == NUL_PTR)
	prefix->name = name;
    else
    {
	new_prefix = my_malloc(sizeof *new_prefix, "addprefix");
	new_prefix->name = expand_tilde(name, 0);
	new_prefix->next = NUL_PTR;
	while (prefix->next != NUL_PTR)
	    prefix = prefix->next;
	prefix->next = new_prefix;
    }
}

PRIVATE void fatal(message)
char *message;
{
    writesn(message);
    killtemps();
    exit(1);
}

PRIVATE char *fixpath(path, prefix, mode)
char *path;
struct prefix_s *prefix;
int mode;
{
    char *ppath;

    for (; prefix != NUL_PTR; prefix = prefix->next)
    {
	if (verbosity > 2)
	{
	    show_who("searching for ");
	    if (mode == R_OK)
		writes("readable file ");
	    else
		writes("executable file ");
	}
	ppath = expand_tilde(stralloc2(prefix->name, path), 1);
	if (verbosity > 2)
	    writesn(ppath);
	if (access(ppath, mode) == 0)
	    return ppath;
	free(ppath);
    }
    return path;
}

PRIVATE void killtemps()
{
    while (tmpargs.argc > START_ARGS)
	my_unlink(tmpargs.argv[--tmpargs.argc]);
}

PRIVATE void *my_malloc(size, where)
unsigned size;
char *where;
{
    void *block;

    if ((block = malloc(size)) == NUL_PTR)
	outofmemory(where);
    return block;
}

PRIVATE char *my_mktemp()
{
    char *p;
    unsigned digit;
    unsigned digits;
    char *template;
    static unsigned tmpnum;

#ifdef MSDOS
    p = template = stralloc2(tmpdir, "/$$YYYXXX");
#else
    p = template = stralloc2(tmpdir, "/bccYYYYXXXX");
#endif
    p += strlen(p);

    digits = getpid();
    while (*--p == 'X')
    {
	if ((digit = digits % 16) > 9)
	    digit += 'A' - ('9' + 1);
	*p = digit + '0';
	digits /= 16;
    }
    digits = tmpnum;
    while (*p == 'Y')
    {
	if ((digit = digits % 16) > 9)
	    digit += 'A' - ('9' + 1);
	*p-- = digit + '0';
	digits /= 16;
    }
    ++tmpnum;
    addarg(&tmpargs, template);
    return template;
}

PRIVATE void my_unlink(name)
char *name;
{
    if (verbosity > 1)
    {
	show_who("unlinking ");
	writesn(name);
    }
    if (verbosity > 4) return;
    if (unlink(name) < 0)
    {
        if( !runerror || verbosity > 1)
	{
	   show_who("error unlinking ");
	   writesn(name);
	   runerror = TRUE;
	}
    }
}

PRIVATE void outofmemory(where)
char *where;
{
    show_who("out of memory in ");
    fatal(where);
}

PRIVATE int run(in_name, out_name, argp)
char *in_name;
char *out_name;
struct arg_s *argp;
{
    int arg0;
    int i;
    int status;

    arg0 = 0;
    if (in_name == NUL_PTR)
	++arg0;
    if (out_name == NUL_PTR)
	arg0 += 2;
    else if (argp->minus_O_broken)
	++arg0;
    if (argp->nr_allocated == 0)
	startarg(argp);
    argp->argv[arg0] = argp->prog;
    i = arg0 + 1;
    if (in_name != NUL_PTR)
	argp->argv[i++] = in_name;
    if (out_name != NUL_PTR)
    {
	if (!argp->minus_O_broken)
	    argp->argv[i++] = "-o";
	argp->argv[i++] = out_name;
    }
    if (verbosity != 0)
    {
	for (i = arg0; i < argp->argc; ++i)
	{
	    writes(argp->argv[i]);
	    writes(" ");
	}
	writen();
    }
    if (verbosity > 4 ) return 0;
#ifdef MSDOS
    status = spawnv(0, argp->prog, argp->argv+arg0);
#else
    switch (fork())
    {
    case -1:
	show_who("fork failed");
	fatal("");
    case 0:
	execv(argp->prog, argp->argv + arg0);
	show_who("exec of ");
	writes(argp->prog);
	fatal(" failed");
    default:
	wait(&status);
	if (status & 0xFF)
	{
	   writes(argp->prog);
	   writesn(": killed by fatal signal");
        }
    }
#endif
    for (i = tmpargs.argc - 1; i >= START_ARGS; --i)
	if (in_name == tmpargs.argv[i])
	{
	    my_unlink(in_name);
	    --tmpargs.argc;
	    memmove(tmpargs.argv + i, tmpargs.argv + i + 1,
		    (tmpargs.argc - i) * sizeof tmpargs.argv[0]);
	    tmpargs.argv[tmpargs.argc] = NUL_PTR;
	    break;
	}
    if (status != 0)
    {
	runerror = TRUE;
	killtemps();
    }
    return status;
}

PRIVATE void set_trap()
{
#ifndef NORDB
#ifdef SIGINT
   signal(SIGINT, trap);
#endif
#ifdef SIGQUIT
   signal(SIGQUIT, trap);
#endif

#else
    /* This is being too trap happy IMO - Rdb */
#ifndef _NSIG
#define _NSIG	NSIG
#endif
    int signum;

    for (signum = 0; signum <= _NSIG; ++signum)
#ifdef SIGCHLD
	if (signum != SIGCHLD)
#endif
	if (signal(signum, SIG_IGN) != SIG_IGN)
	    signal(signum, trap);
#endif
}

PRIVATE void show_who(message)
char *message;
{
#ifdef MSDOS
    char * ptr;
    ptr = strrchr(progname, '\\');
    if(ptr) ptr++; else ptr = progname;
    writes(ptr);
#else
    writes(progname);
#endif
    writes(": ");
    writes(message);
}

PRIVATE void startarg(argp)
struct arg_s *argp;
{
    argp->argv = my_malloc((argp->nr_allocated = ALLOC_UNIT)
			   * sizeof *argp->argv, "startarg");
    argp->argc = START_ARGS;
    argp->argv[START_ARGS] = NUL_PTR;
}

PRIVATE char *stralloc(s)
char *s;
{
    return strcpy(my_malloc(strlen(s) + 1, "stralloc"), s);
}

PRIVATE char *stralloc2(s1, s2)
char *s1;
char *s2;
{
    return strcat(strcpy(my_malloc(
	strlen(s1) + strlen(s2) + 1, "stralloc2"), s1), s2);
}

PRIVATE void trap(signum)
int signum;
{
    signal(signum, SIG_IGN);
    show_who("caught signal");
    fatal("");
}

PRIVATE void unsupported(option, message)
char *option;
char *message;
{
    show_who("compiler option ");
    writes(option);
    writes(" (");
    writes(message);
    writesn(") not supported yet");
}

PRIVATE void writen()
{
    writes("\n");
}

PRIVATE void writes(s)
char *s;
{
    write(2, s, strlen(s));
}

PRIVATE void writesn(s)
char *s;
{
    writes(s);
    writen();
}