diet.c

#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <write12.h>

#include "dietfeatures.h"

/* goal:
 *   when invoked as
 * "diet gcc -c t.c"
 *   exec
 * "gcc -I/path/to/dietlibc/include -c t.c"
 *
 *   when invoked as
 * "diet sparc-linux-gcc -o t t.o"
 *   exec
 * "sparc-linux-gcc -nostdlib -static -o t t.o /path/to/dietlibc/bin-sparc/start.o /path/to/dietlibc/bin-sparc/dietlibc.a"
*/

static void error(const char *message) {
  __write2(message);
  exit(1);
}

static const char* Os[] = {
  "i386","-Os","-mpreferred-stack-boundary=4",
	 "-falign-functions=1","-falign-jumps=1",
	 "-falign-loops=1","-fomit-frame-pointer",0,
  "x86_64","-Os",0,
  "x32","-Os",0,
  "sparc","-Os","-mcpu=supersparc",0,
  "sparc64","-Os","-m64","-mhard-quad-float",0,
  "alpha","-Os","-fomit-frame-pointer",0,
  "arm","-Os","-fomit-frame-pointer",0,
  "aarch64","-Os","-fomit-frame-pointer",0,
  "mips","-Os","-fomit-frame-pointer","-march=mips2",0,
  "mipsel","-Os","-fomit-frame-pointer","-march=mips2",0,
  "mips64","-Os","-fomit-frame-pointer",0,
  "ppc","-Os","-fomit-frame-pointer","-mpowerpc-gpopt","-mpowerpc-gfxopt",0,
  "ppc64","-Os","-fomit-frame-pointer","-mpowerpc-gpopt","-mpowerpc-gfxopt",0,
  "ppc64le","-Os","-fomit-frame-pointer","-mpowerpc-gpopt","-mpowerpc-gfxopt",0,
  "s390","-Os","-fomit-frame-pointer",0,
  "s390x","-Os","-fomit-frame-pointer",0,
  "sh","-Os","-fomit-frame-pointer",0,
  "ia64","-Os","-fno-omit-frame-pointer",0,
  0};

static void usage(void) {
  __write2(
#ifdef __DYN_LIB
	   "dyn-"
#endif
	   "diet version " VERSION
#ifndef INSTALLVERSION
	   " (non-install version in source tree)"
#endif
	   "\n\n");
  error("usage: diet [-v] [-Os] gcc command line\n"
	"e.g.   diet -Os gcc -c t.c\n"
	"or     diet sparc-linux-gcc -o foo foo.c bar.o\n");
}

int main(int argc,char *argv[]) {
  int _link=0;
  int compile=0;
  int preprocess=0;
  int verbose=0;
  int profile=0;
  char* diethome;
  char* platform;
#ifdef __DYN_LIB
  int shared=0;
#endif
  char* shortplatform=0;
#ifdef WANT_SAFEGUARD
  char safeguard1[]="-include";
  char* safeguard2;
#endif
  const char *nostdlib="-nostdlib";
  const char *libgcc="-lgcc";
  char *libpthread="-lpthread";
  char dashL[1000];
  char dashstatic[]="-static";
  int i;
  int mangleopts=0;
  int printpath=0;
  char manglebuf[1024];
  int m,pie;

  if (!(diethome = getenv("DIETHOME")))
    diethome=DIETHOME;
#ifdef WANT_SAFEGUARD
  safeguard2=alloca(strlen(diethome)+30);
  strcpy(safeguard2, diethome);
  strcat(safeguard2, "/include/dietref.h");
#endif
  platform=alloca(strlen(diethome)+100);
  strcpy(platform,diethome);
#ifdef INSTALLVERSION
  strcat(platform,"/lib-");
#else
#ifndef __DYN_LIB
  strcat(platform,"/bin-");
#else
  strcat(platform,"/pic-");
#endif
#endif
  strcpy(dashL,"-L");

  do {
    if (!argv[1]) usage();
    if (!strcmp(argv[1],"-v")) {
      ++argv; --argc;
      verbose=1;
    } else if (!strcmp(argv[1],"-Os")) {
      ++argv; --argc;
      mangleopts=1;
    } else if (!strcmp(argv[1],"-L")) {
      ++argv; --argc;
      printpath=1;
    } else break;
  } while (1);
  {
    m=0;
    pie=0;
    for (i=1; i<argc; ++i) {
      if (!strcmp(argv[i],"-m32")) m=32; else
      if (!strcmp(argv[i],"-mx32")) m=33; else
      if (!strcmp(argv[i],"-m64")) m=64; else
      if (!strcmp(argv[i],"-pie")) pie=1; else
      if (!strcmp(argv[i],"-fpie")) pie=1; else
      if (!strcmp(argv[i],"-fno-pie")) pie=0;
    }
  }
  {
    char *cc=argv[1];
    char *tmp=strchr(cc,0)-2;
    char *tmp2,*tmp3;
    if (tmp<cc) goto donttouch;
    if (!strstr(cc,"cc") && !strstr(cc,"clang")) goto donttouch;
    if ((tmp2=strstr(cc,"linux-"))) {	/* cross compiling? */
      int len=strlen(platform);
      --tmp2;
      tmp3=strchr(cc,'-');
      if (tmp3<tmp2) tmp2=tmp3;
      if (tmp2-cc>90) error("platform name too long!\n");
      shortplatform=platform+len;
      memmove(shortplatform,argv[1],(size_t)(tmp2-cc));
      platform[tmp2-cc+len]=0;
      if (shortplatform[0]=='i' && shortplatform[2]=='8' && shortplatform[3]=='6') shortplatform[1]='3';
      if (!strncmp(shortplatform, "powerpc", 7)) {
        shortplatform[0] = shortplatform[1] = 'p'; shortplatform[2] = 'c';
        memmove(&shortplatform[3], &shortplatform[7], strlen(&shortplatform[7]) + 1);
      }
      if (!strcmp(shortplatform, "hppa"))
        strcpy(shortplatform, "parisc");
      if (!strcmp(shortplatform, "mips64el"))
        strcpy(shortplatform, "mips64");
      if (!strncmp(cc, "x86_64-linux-gnux32-", 20) || !strncmp(cc, "x86_64-pc-linux-gnux32-", 23))
        strcpy(shortplatform, "x32");
    } else {
#ifdef __sparc__
#ifdef __arch64__
      shortplatform="sparc64";
#else
      shortplatform="sparc";
#endif
#endif
#ifdef __powerpc__
      shortplatform="ppc";
#endif
#ifdef __powerpc64__
#ifdef __LITTLE_ENDIAN__
      shortplatform="ppc64le";
#else
      shortplatform="ppc64";
#endif
#endif
#ifdef __i386__
      shortplatform="i386";
#endif
#ifdef __alpha__
      shortplatform="alpha";
#endif
#ifdef __arm__
      shortplatform="arm";
#endif
#ifdef __aarch64__
      shortplatform="aarch64";
#endif
#ifdef __mips64__
      shortplatform="mips64";
#else
#ifdef __MIPSEL__
      shortplatform="mipsel";
#endif
#ifdef __MIPSEB__
      shortplatform="mips";
#endif
#endif
#ifdef __s390x__
      shortplatform="s390x";
#else
#ifdef __s390__
      shortplatform="s390";
#endif
#endif
#ifdef __sh__
      shortplatform="sh";
#endif
#ifdef __hppa__
      shortplatform="parisc";
#endif
#ifdef __x86_64__
      shortplatform=(m==32?"i386":(m==33?"x32":"x86_64"));
#endif
#ifdef __ia64__
      shortplatform="ia64";
#endif
      {
	char *tmp4=platform+strlen(platform);
	strcpy(tmp4,shortplatform);
	shortplatform=tmp4;
      }
    }
    /* MIPS needs special handling.  If argv contains -EL, change
     * platform name to mipsel */
    if (!strcmp(shortplatform,"mips")) {
      for (i=1; i<argc; ++i)
	if (!strcmp(argv[i],"-EL"))
	  strcpy(shortplatform,"mipsel");
    }
    if (printpath) {
      write(1,platform,strlen(platform));
      return 0;
    }
    strcat(dashL,platform);
    if (strcmp(tmp,"ld")) {
      char **newargv;
      char **dest;
      char *a,*b,*c;
#if defined(WANT_DYNAMIC) || defined(WANT_CTOR) || defined(WANT_EXCEPTIONS)
      char *d,*e;
#endif
#ifdef __DYN_LIB
      char *f;
#endif
      char *g=0;
/* we need to add -I... if the command line contains -c, -S or -E */
      for (i=2; i<argc; ++i) {
	if (argv[i][0]=='-') {
	  if (argv[i][1]=='M')
	    goto pp;
	  else if (argv[i][1]=='g') {
	    g=alloca(strlen(platform)+20);
	    strcpy(g,platform);
	    strcat(g,"/stackgap-g.o");
	  }
	}
	if (!strcmp(argv[i],"-pg"))
	  profile=1;
	else if (!strcmp(argv[i],"-c") || !strcmp(argv[i],"-S"))
	  compile=1;
	else if (!strcmp(argv[i],"-E"))
pp:
	  preprocess=compile=1;
      }
/* we need to add -nostdlib if we are not compiling */
      _link=!compile;
#ifdef __DYN_LIB
      if (_link) {
	for (i=2; i<argc; ++i)
	  if (!strcmp(argv[i],"-shared")) {
	    shared=1;
	    _link=0;
	  }
      }
#endif
#if 0
      for (i=2; i<argc; ++i)
	if (!strcmp(argv[i],"-o"))
	  if (!compile) _link=1;
#endif

      newargv=alloca(sizeof(char*)*(argc+100));
      a=alloca(strlen(diethome)+20);
      b=alloca(strlen(platform)+20);
      c=alloca(strlen(platform)+20);

      strcpy(a,diethome); strcat(a,"/include");
#ifndef __DYN_LIB
      strcpy(b,platform);
      if (profile)
	strcat(b,"/pstart.o");
      else
	strcat(b,pie ? "/start-pie.o" : "/start.o");
#ifdef INSTALLVERSION
      strcpy(c,platform); strcat(c,"/libc.a");
#else
      strcpy(c,platform); strcat(c,"/dietlibc.a");
#endif
#else
      strcpy(b,platform); strcat(b,"/dstart.o");
      strcpy(c,"-lc");
#endif

#ifdef WANT_DYNAMIC
      d=alloca(strlen(platform)+20);
      e=alloca(strlen(platform)+20);
#ifdef __DYN_LIB
      strcpy(d,platform);
      strcpy(e,platform);
      if (shared)
	strcat(d,"/dyn_so_start.o");
#ifdef INSTALLVERSION
      else
	strcat(d,"/dyn_dstart.o");
      strcat(e,"/dyn_dstop.o");
#else
      else
	strcat(d,"/dyn_start.o");
      strcat(e,"/dyn_stop.o");
#endif
#else
      strcpy(d,platform); strcat(d,"/dyn_start.o");
      strcpy(e,platform); strcat(e,"/dyn_stop.o");
#endif

#elif defined(WANT_CTOR) || defined(WANT_EXCEPTIONS)
      e=alloca(strlen(platform)+20);
      strcpy(e,platform);
      strcat(e,"/crtend.o");
#endif

      dest=newargv;
      *dest++=argv[1];
      if (argv[2]) {
	if (!strcmp(argv[2],"-V")) {
	  *dest++=argv[2];
	  *dest++=argv[3];
	  argv+=2;
	  argc-=2;
	} else if (!memcmp(argv[2],"-V",2)) {
	  *dest++=argv[2];
	  ++argv;
	  --argc;
	}
      }
#ifndef __DYN_LIB
      if (_link) {
	*dest++=(char*)nostdlib;
	if (pie) {
	  *dest++="-Wl,-pie";
	  *dest++="-Wl,--no-dynamic-linker";
	} else
	  *dest++=dashstatic;
	*dest++=dashL;
      }
#else
      /* avoid R_*_COPY relocations */
      *dest++="-fPIC";
      if (_link || shared) { *dest++=(char*)nostdlib; *dest++=dashL; }
#endif
#ifdef WANT_SAFEGUARD
      if (compile && !preprocess) {
	*dest++=safeguard1;
	*dest++=safeguard2;
      }
#endif
      if (_link) { *dest++=b; if (g && !pie) *dest++=g; }
#ifdef WANT_DYNAMIC
      if (_link) { *dest++=d; }
#endif
      for (i=2; i<argc; ++i) {
	if (!strcmp(argv[i],"-pthread")) {
	  *dest++="-D_REENTRANT";
	  if (_link) *dest++="-lpthread";
	  continue;
	}
#if 0
	if (mangleopts)
	  if (argv[i][0]=='-' && (argv[i][1]=='O' || argv[i][1]=='f' ||
				  (argv[i][1]=='m' && argv[i][2]!='3' && argv[i][2]!='6' && argv[i][2]!='x'))) {
	    if (strcmp(argv[i],"-fpic") && strcmp(argv[i],"-fno-pic") &&
		strcmp(argv[i],"-fpie") && strcmp(argv[i],"-fno-pie") &&
		strncmp(argv[i],"-fvisibility=",13))
	      continue;
	  }
#endif
	*dest++=argv[i];
      }
#ifndef __DYN_LIB
      if (compile || _link) {
	*dest++="-isystem";
	*dest++=a;
      }
#else
      if (compile || _link || shared) {
	*dest++="-isystem";
	*dest++=a;
      }
#endif
      *dest++="-D__dietlibc__";
      if (mangleopts) {
	const char **o=Os;

	{
	  int fd;
	  tmp=getenv("HOME");
	  if (tmp) {
	    if (strlen(tmp)+strlen(cc)<900) {
	      strcpy(manglebuf,tmp);
	      strcat(manglebuf,"/.diet/");
	      tmp=strrchr(cc,'/');
	      if (tmp) ++tmp; else tmp=cc;
	      strcat(manglebuf,tmp);
	      if ((fd=open(manglebuf,O_RDONLY))>=0) {
		int len=read(fd,manglebuf,1023);
		if (len>0) {
		  manglebuf[len]=0;
		  *dest++=manglebuf;
		  for (i=1; i<len; ++i) {
		    if (manglebuf[i]==' ' || manglebuf[i]=='\n') {
		      manglebuf[i]=0;
		      if (i+1<len)
			*dest++=manglebuf+i+1;
		    }
		  }
		  goto incorporated;
		}
	      }
	    }
	  }
	}
	for (o=Os;*o;++o) {
	  if (!strcmp(*o,shortplatform)) {
	    ++o;
	    while (*o) {
	      *dest++=(char*)*o;
	      ++o;
	    }
	    break;
	  } else
	    while (*o) ++o;
	}
      }
incorporated:
      if (_link) {
	if (profile) *dest++="-lgmon";
	*dest++=c; *dest++=(char*)libgcc;
	if (!strcmp(shortplatform,"sparc") ||
	    !strcmp(shortplatform,"sparc64") ||
	    !strncmp(shortplatform,"arm",3)) {
	  *dest++=c;
	}
      }
#if defined(WANT_DYNAMIC) || defined(WANT_CTOR) || defined(WANT_EXCEPTIONS)
      if (_link) { *dest++=e; }
#endif
#ifdef __DYN_LIB
      if (shared){ *dest++=c; }
      f=alloca(strlen(platform)+100);
      if (_link) {
	strcpy(f,"-Wl,-dynamic-linker=");
	strcat(f,platform);
//	strcat(f,"/diet-linux.so");
	strcat(f,"/libdl.so");
	*dest++=f;
      }
#endif
      *dest=0;
      if (verbose) {
	for (i=0; newargv[i]; i++) {
	  __write2(newargv[i]);
	  __write2(" ");
	}
	__write2("\n");
      }
      execvp(newargv[0],newargv);
      goto error;
    }
  }
donttouch:
  execvp(argv[1],argv+1);
error:
  error("execvp() failed!\n");
  return 1;
}