tools/cw/cw.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright 2018 Richard Lowe.
 * Copyright 2019 Joyent, Inc.
 */

/*
 * Wrapper for the GNU C compiler to make it accept the Sun C compiler
 * arguments where possible.
 *
 * Since the translation is inexact, this is something of a work-in-progress.
 *
 */

/*
 * If you modify this file, you must increment CW_VERSION.  This is a semver,
 * incompatible changes should bump the major, anything else the minor.
 */
#define	CW_VERSION	"9.0"

/*
 * -#		Verbose mode
 * -###		Show compiler commands built by driver, no compilation
 * -A<name[(tokens)]>	Preprocessor predicate assertion
 * -C		Prevent preprocessor from removing comments
 * -c		Compile only - produce .o files, suppress linking
 * -D<name[=token]>	Associate name with token as if by #define
 * -d[y|n]	dynamic [-dy] or static [-dn] option to linker
 * -E		Compile source through preprocessor only, output to stdout
 * -erroff=<t>	Suppress warnings specified by tags t(%none, %all, <tag list>)
 * -errtags=<a>	Display messages with tags a(no, yes)
 * -errwarn=<t>	Treats warnings specified by tags t(%none, %all, <tag list>)
 *		as errors
 * -g		Compile for debugging
 * -H		Print path name of each file included during compilation
 * -h <name>	Assign <name> to generated dynamic shared library
 * -I<dir>	Add <dir> to preprocessor #include file search path
 * -i		Passed to linker to ignore any LD_LIBRARY_PATH setting
 * -keeptmp	Keep temporary files created during compilation
 * -L<dir>	Pass to linker to add <dir> to the library search path
 * -l<name>	Link with library lib<name>.a or lib<name>.so
 * -mt		Specify options needed when compiling multi-threaded code
 * -O		Use default optimization level (-xO2 or -xO3. Check man page.)
 * -o <outputfile> Set name of output file to <outputfile>
 * -P		Compile source through preprocessor only, output to .i  file
 * -p		Compile for profiling with prof
 * -R<dir[:dir]> Build runtime search path list into executable
 * -S		Compile and only generate assembly code (.s)
 * -s		Strip symbol table from the executable file
 * -t		Turn off duplicate symbol warnings when linking
 * -U<name>	Delete initial definition of preprocessor symbol <name>
 * -V		Report version number of each compilation phase
 * -v		Do stricter semantic checking
 * -W<c>,<arg>	Pass <arg> to specified component <c> (a,l,m,p,0,2,h,i,u)
 * -w		Suppress compiler warning messages
 * -Xa		Compile assuming ANSI C conformance, allow K & R extensions
 *		(default mode)
 * -Xs		Compile assuming (pre-ANSI) K & R C style code
 * -xarch=<a>	Specify target architecture instruction set
 * -xbuiltin[=<b>] When profitable inline, or substitute intrinisic functions
 *		for system functions, b={%all,%none}
 * -xchip=<c>	Specify the target processor for use by the optimizer
 * -xO<n>	Generate optimized code (n={1|2|3|4|5})
 * -xtarget=<t>	Specify target system for optimization
 * -YI,<dir>	Specify <dir> for location of headers
 */

/*
 * Translation table:
 */
/*
 * -#				-v
 * -###				error
 * -A<name[(tokens)]>		pass-thru
 * -B<[static|dynamic]>		pass-thru (syntax error for anything else)
 * -C				pass-thru
 * -c				pass-thru
 * -D<name[=token]>		pass-thru
 * -E				pass-thru
 * -errtags=%all		-Wall
 * -errwarn=%all		-Werror else -Wno-error
 * -g				pass-thru
 * -H				pass-thru
 * -I<dir>			pass-thru
 * -i				pass-thru
 * -keeptmp			-save-temps
 * -L<dir>			pass-thru
 * -l<name>			pass-thru
 * -mt				-D_REENTRANT
 * -nolib			-nodefaultlibs
 * -O				-O1 (Check the man page to be certain)
 * -o <outputfile>		pass-thru
 * -P				-E -o filename.i (or error)
 * -p				pass-thru
 * -R<dir[:dir]>		pass-thru
 * -S				pass-thru
 * -U<name>			pass-thru
 * -V				--version
 * -v				-Wall
 * -Wa,<arg>			pass-thru
 * -Wp,<arg>			pass-thru
 * -Wl,<arg>			pass-thru
 * -xmodel=kernel		-ffreestanding -mcmodel=kernel -mno-red-zone
 * -Wu,-save_args		-msave-args
 * -w				pass-thru
 * -Xa				-std=iso9899:199409 or -ansi
 * -Xs				-traditional -std=c89
 * -xarch=<a>			table
 * -xbuiltin[=<b>]		-fbuiltin (-fno-builtin otherwise)
 * -xchip=<c>			table
 * -xO<n>			-O<n>
 * -xtarget=<t>			table
 * -xtransition			-Wtransition
 * -YI,<dir>			-nostdinc -I<dir>
 */

#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <unistd.h>
#include <dirent.h>

#include <sys/param.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/utsname.h>
#include <sys/wait.h>

#define	CW_F_CXX	0x01
#define	CW_F_SHADOW	0x02
#define	CW_F_EXEC	0x04
#define	CW_F_ECHO	0x08
#define	CW_F_XLATE	0x10
#define	CW_F_PROG	0x20

typedef enum cw_op {
	CW_O_NONE = 0,
	CW_O_PREPROCESS,
	CW_O_COMPILE,
	CW_O_LINK
} cw_op_t;

struct aelist {
	struct ae {
		struct ae *ae_next;
		char *ae_arg;
	} *ael_head, *ael_tail;
	int ael_argc;
};

typedef enum {
	GNU,
	SUN,
	SMATCH
} compiler_style_t;

typedef struct {
	char *c_name;
	char *c_path;
	compiler_style_t c_style;
} cw_compiler_t;

typedef struct cw_ictx {
	struct cw_ictx	*i_next;
	cw_compiler_t	*i_compiler;
	char		*i_linker;
	struct aelist	*i_ae;
	uint32_t	i_flags;
	int		i_oldargc;
	char		**i_oldargv;
	pid_t		i_pid;
	char		*i_tmpdir;
	char		*i_stderr;
} cw_ictx_t;

/*
 * Status values to indicate which Studio compiler and associated
 * flags are being used.
 */
#define	M32		0x01	/* -m32 - only on Studio 12 */
#define	M64		0x02	/* -m64 - only on Studio 12 */
#define	SS11		0x100	/* Studio 11 */
#define	SS12		0x200	/* Studio 12 */

#define	TRANS_ENTRY	5
/*
 * Translation table definition for the -xarch= flag. The "x_arg"
 * value is translated into the appropriate gcc flags according
 * to the values in x_trans[n]. The x_flags indicates what compiler
 * is being used and what flags have been set via the use of
 * "x_arg".
 */
typedef struct xarch_table {
	char	*x_arg;
	int	x_flags;
	char	*x_trans[TRANS_ENTRY];
} xarch_table_t;

/*
 * The translation table for the -xarch= flag used in the Studio compilers.
 */
static const xarch_table_t xtbl[] = {
#if defined(__x86)
	{ "generic",	SS11, {NULL} },
	{ "generic64",	(SS11|M64), { "-m64", "-mtune=opteron" } },
	{ "amd64",	(SS11|M64), { "-m64", "-mtune=opteron" } },
	{ "386",	SS11,	{ "-march=i386" } },
	{ "pentium_pro", SS11,	{ "-march=pentiumpro" } },
	{ "sse",	SS11, { "-msse", "-mfpmath=sse" } },
	{ "sse2",	SS11, { "-msse2", "-mfpmath=sse" } },
#endif
};

static int xtbl_size = sizeof (xtbl) / sizeof (xarch_table_t);

static const char *xchip_tbl[] = {
#if defined(__x86)
	"386",		"-mtune=i386", NULL,
	"486",		"-mtune=i486", NULL,
	"pentium",	"-mtune=pentium", NULL,
	"pentium_pro",  "-mtune=pentiumpro", NULL,
#endif
	NULL,		NULL
};

static const char *xtarget_tbl[] = {
#if defined(__x86)
	"pentium_pro",	"-march=pentiumpro", NULL,
#endif	/* __x86 */
	NULL,		NULL
};

static void
nomem(void)
{
	errx(1, "out of memory");
}

static void
newae(struct aelist *ael, const char *arg)
{
	struct ae *ae;

	if ((ae = calloc(1, sizeof (*ae))) == NULL)
		nomem();
	ae->ae_arg = strdup(arg);
	if (ael->ael_tail == NULL)
		ael->ael_head = ae;
	else
		ael->ael_tail->ae_next = ae;
	ael->ael_tail = ae;
	ael->ael_argc++;
}

static cw_ictx_t *
newictx(void)
{
	cw_ictx_t *ctx = calloc(1, sizeof (cw_ictx_t));
	if (ctx)
		if ((ctx->i_ae = calloc(1, sizeof (struct aelist))) == NULL) {
			free(ctx);
			return (NULL);
		}

	return (ctx);
}

static void
error(const char *arg)
{
	errx(2, "error: mapping failed at or near arg '%s'", arg);
}

/*
 * Add the current favourite set of warnings to the gcc invocation.
 */
static void
warnings(struct aelist *h)
{
	static int warningsonce;

	if (warningsonce++)
		return;

	/*
	 * Enable as many warnings as exist, then disable those that we never
	 * ever want.
	 */
	newae(h, "-Wall");
	newae(h, "-Wextra");
}

static void
optim_disable(struct aelist *h, int level)
{
	if (level >= 2) {
		newae(h, "-fno-strict-aliasing");
		newae(h, "-fno-unit-at-a-time");
		newae(h, "-fno-optimize-sibling-calls");
	}
}

static void
Xsmode(struct aelist *h)
{
	static int xsonce;

	if (xsonce++)
		return;

	newae(h, "-traditional");
	newae(h, "-traditional-cpp");
}

static void
usage(void)
{
	extern char *__progname;
	(void) fprintf(stderr,
	    "usage: %s [-C] [--versions] --primary <compiler> "
	    "[--shadow <compiler>]... -- cflags...\n",
	    __progname);
	(void) fprintf(stderr, "compilers take the form: name,path,style\n"
	    " - name: a unique name usable in flag specifiers\n"
	    " - path: path to the compiler binary\n"
	    " - style: the style of flags expected: either sun or gnu\n");
	exit(2);
}

static int
xlate_xtb(struct aelist *h, const char *xarg)
{
	int	i, j;

	for (i = 0; i < xtbl_size; i++) {
		if (strcmp(xtbl[i].x_arg, xarg) == 0)
			break;
	}

	/*
	 * At the end of the table and so no matching "arg" entry
	 * found and so this must be a bad -xarch= flag.
	 */
	if (i == xtbl_size)
		error(xarg);

	for (j = 0; j < TRANS_ENTRY; j++) {
		if (xtbl[i].x_trans[j] != NULL)
			newae(h, xtbl[i].x_trans[j]);
		else
			break;
	}
	return (xtbl[i].x_flags);

}

static void
xlate(struct aelist *h, const char *xarg, const char **table)
{
	while (*table != NULL && strcmp(xarg, *table) != 0) {
		while (*table != NULL)
			table++;
		table++;
	}

	if (*table == NULL)
		error(xarg);

	table++;

	while (*table != NULL) {
		newae(h, *table);
		table++;
	}
}

/*
 * The compiler wants the output file to end in appropriate extension.  If
 * we're generating a name from whole cloth (path == NULL), we assume that
 * extension to be .o, otherwise we match the extension of the caller.
 */
static char *
discard_file_name(cw_ictx_t *ctx, const char *path)
{
	char *ret, *ext;
	char tmpl[] = "cwXXXXXX";

	if (path == NULL) {
		ext = ".o";
	} else {
		ext = strrchr(path, '.');
	}

	/*
	 * We need absolute control over where the temporary file goes, since
	 * we rely on it for cleanup so tempnam(3C) and tmpnam(3C) are
	 * inappropriate (they use TMPDIR, preferentially).
	 *
	 * mkstemp(3C) doesn't actually help us, since the temporary file
	 * isn't used by us, only its name.
	 */
	if (mktemp(tmpl) == NULL)
		nomem();

	(void) asprintf(&ret, "%s/%s%s", ctx->i_tmpdir, tmpl,
	    (ext != NULL) ? ext : "");

	if (ret == NULL)
		nomem();

	return (ret);
}

static bool
is_source_file(const char *path)
{
	char *ext = strrchr(path, '.');

	if ((ext == NULL) || (*(ext + 1) == '\0'))
		return (false);

	ext += 1;

	if ((strcasecmp(ext, "c") == 0) ||
	    (strcmp(ext, "cc") == 0) ||
	    (strcmp(ext, "i") == 0) ||
	    (strcasecmp(ext, "s") == 0) ||
	    (strcmp(ext, "cpp") == 0)) {
		return (true);
	}

	return (false);
}

static bool
is_asm_file(const char *path)
{
	char *ext = strrchr(path, '.');

	if ((ext == NULL) || (*(ext + 1) == '\0'))
		return (false);

	ext += 1;

	if (strcasecmp(ext, "s") == 0)
		return (true);

	return (false);
}

static void
do_gcc(cw_ictx_t *ctx)
{
	int c;
	int nolibc = 0;
	int in_output = 0, seen_o = 0, c_files = 0;
	cw_op_t op = CW_O_LINK;
	char *model = NULL;
	char *nameflag;
	int mflag = 0;

	if (ctx->i_flags & CW_F_PROG) {
		newae(ctx->i_ae, "--version");
		return;
	}

	newae(ctx->i_ae, "-fident");
	newae(ctx->i_ae, "-finline");
	newae(ctx->i_ae, "-fno-inline-functions");
	newae(ctx->i_ae, "-fno-builtin");
	newae(ctx->i_ae, "-fno-asm");
	newae(ctx->i_ae, "-fdiagnostics-show-option");
	newae(ctx->i_ae, "-nodefaultlibs");

	/*
	 * This is needed because 'u' is defined
	 * under a conditional on 'sun'.  Should
	 * probably just remove the conditional,
	 * or make it be dependent on '__sun'.
	 *
	 * -Dunix is also missing in enhanced ANSI mode
	 */
	newae(ctx->i_ae, "-D__sun");

	if (asprintf(&nameflag, "-_%s=", ctx->i_compiler->c_name) == -1)
		nomem();

	/*
	 * Walk the argument list, translating as we go ..
	 */
	while (--ctx->i_oldargc > 0) {
		char *arg = *++ctx->i_oldargv;
		size_t arglen = strlen(arg);

		if (*arg == '-') {
			arglen--;
		} else {
			if (!in_output && is_source_file(arg))
				c_files++;

			/*
			 * Otherwise, filenames and partial arguments
			 * are passed through for gcc to chew on.  However,
			 * output is always discarded for the secondary
			 * compiler.
			 */
			if ((ctx->i_flags & CW_F_SHADOW) && in_output) {
				newae(ctx->i_ae, discard_file_name(ctx, arg));
			} else {
				newae(ctx->i_ae, arg);
			}
			in_output = 0;
			continue;
		}

		if (ctx->i_flags & CW_F_CXX) {
			if (strncmp(arg, "-_g++=", 6) == 0) {
				newae(ctx->i_ae, strchr(arg, '=') + 1);
				continue;
			}

			if (strcmp(arg, "-xwe") == 0) {
				/* turn warnings into errors */
				newae(ctx->i_ae, "-Werror");
				continue;
			}
			if (strcmp(arg, "-nolib") == 0) {
				/* -nodefaultlibs is on by default */
				nolibc = 1;
				continue;
			}
		}

		switch ((c = arg[1])) {
		case '_':
			if ((strncmp(arg, nameflag, strlen(nameflag)) == 0) ||
			    (strncmp(arg, "-_gcc=", 6) == 0) ||
			    (strncmp(arg, "-_gnu=", 6) == 0)) {
				newae(ctx->i_ae, strchr(arg, '=') + 1);
			}
			break;
		case '#':
			if (arglen == 1) {
				newae(ctx->i_ae, "-v");
				break;
			}
			error(arg);
			break;
		case 'f':
			if ((strcmp(arg, "-fpic") == 0) ||
			    (strcmp(arg, "-fPIC") == 0)) {
				newae(ctx->i_ae, arg);
				break;
			}
			error(arg);
			break;
		case 'E':
			if (arglen == 1) {
				newae(ctx->i_ae, "-xc");
				newae(ctx->i_ae, arg);
				op = CW_O_PREPROCESS;
				nolibc = 1;
				break;
			}
			error(arg);
			break;
		case 'c':
		case 'S':
			if (arglen == 1) {
				op = CW_O_COMPILE;
				nolibc = 1;
			}
			/* FALLTHROUGH */
		case 'C':
		case 'H':
		case 'p':
			if (arglen == 1) {
				newae(ctx->i_ae, arg);
				break;
			}
			error(arg);
			break;
		case 'A':
		case 'g':
		case 'I':
		case 'i':
		case 'L':
		case 'l':
		case 'R':
		case 'U':
		case 'u':
		case 'w':
			newae(ctx->i_ae, arg);
			break;
		case 'o':
			seen_o = 1;
			if (arglen == 1) {
				in_output = 1;
				newae(ctx->i_ae, arg);
			} else if (ctx->i_flags & CW_F_SHADOW) {
				newae(ctx->i_ae, "-o");
				newae(ctx->i_ae, discard_file_name(ctx, arg));
			} else {
				newae(ctx->i_ae, arg);
			}
			break;
		case 'D':
			newae(ctx->i_ae, arg);
			/*
			 * XXX	Clearly a hack ... do we need _KADB too?
			 */
			if (strcmp(arg, "-D_KERNEL") == 0 ||
			    strcmp(arg, "-D_BOOT") == 0)
				newae(ctx->i_ae, "-ffreestanding");
			break;
		case 'e':
			if (strcmp(arg, "-errtags=yes") == 0) {
				warnings(ctx->i_ae);
				break;
			}
			if (strcmp(arg, "-errwarn=%all") == 0) {
				newae(ctx->i_ae, "-Werror");
				break;
			}
			error(arg);
			break;
		case 'k':
			if (strcmp(arg, "-keeptmp") == 0) {
				newae(ctx->i_ae, "-save-temps");
				break;
			}
			error(arg);
			break;
		case 'm':
			if (strcmp(arg, "-mt") == 0) {
				newae(ctx->i_ae, "-D_REENTRANT");
				break;
			}
			if (strcmp(arg, "-m64") == 0) {
				newae(ctx->i_ae, "-m64");
#if defined(__x86)
				newae(ctx->i_ae, "-mtune=opteron");
#endif
				mflag |= M64;
				break;
			}
			if (strcmp(arg, "-m32") == 0) {
				newae(ctx->i_ae, "-m32");
				mflag |= M32;
				break;
			}
			error(arg);
			break;
		case 'O':
			if (arglen == 1) {
				newae(ctx->i_ae, "-O");
				break;
			}
			error(arg);
			break;
		case 'P':
			/*
			 * We could do '-E -o filename.i', but that's hard,
			 * and we don't need it for the case that's triggering
			 * this addition.  We'll require the user to specify
			 * -o in the Makefile.  If they don't they'll find out
			 * in a hurry.
			 */
			newae(ctx->i_ae, "-E");
			op = CW_O_PREPROCESS;
			nolibc = 1;
			break;
		case 's':
			if (strcmp(arg, "-shared") == 0) {
				newae(ctx->i_ae, "-shared");
				nolibc = 1;
				break;
			}
			error(arg);
			break;

		case 'V':
			if (arglen == 1) {
				ctx->i_flags &= ~CW_F_ECHO;
				newae(ctx->i_ae, "--version");
				break;
			}
			error(arg);
			break;
		case 'v':
			if (arglen == 1) {
				warnings(ctx->i_ae);
				break;
			}
			error(arg);
			break;
		case 'W':
			if (strncmp(arg, "-Wa,", 4) == 0 ||
			    strncmp(arg, "-Wp,", 4) == 0 ||
			    strncmp(arg, "-Wl,", 4) == 0) {
				newae(ctx->i_ae, arg);
				break;
			}

#if defined(__x86)
			if (strcmp(arg, "-Wu,-save_args") == 0) {
				newae(ctx->i_ae, "-msave-args");
				break;
			}
#endif	/* __x86 */
			error(arg);
			break;
		case 'X':
			if (strcmp(arg, "-Xs") == 0) {
				Xsmode(ctx->i_ae);
				break;
			}
			error(arg);
			break;
		case 'x':
			if (arglen == 1)
				error(arg);
			switch (arg[2]) {
			case 'a':
				if (strncmp(arg, "-xarch=", 7) == 0) {
					mflag |= xlate_xtb(ctx->i_ae, arg + 7);
					break;
				}
				error(arg);
				break;
			case 'b':
				if (strncmp(arg, "-xbuiltin=", 10) == 0) {
					if (strcmp(arg + 10, "%all"))
						newae(ctx->i_ae, "-fbuiltin");
					break;
				}
				error(arg);
				break;
			case 'c':
				if (strncmp(arg, "-xc99=%all", 10) == 0) {
					newae(ctx->i_ae, "-std=gnu99");
					break;
				}
				if (strncmp(arg, "-xc99=%none", 11) == 0) {
					newae(ctx->i_ae, "-std=gnu89");
					break;
				}
				if (strncmp(arg, "-xchip=", 7) == 0) {
					xlate(ctx->i_ae, arg + 7, xchip_tbl);
					break;
				}

				error(arg);
				break;
#if defined(__x86)
			case 'm':
				if (strcmp(arg, "-xmodel=kernel") == 0) {
					newae(ctx->i_ae, "-ffreestanding");
					newae(ctx->i_ae, "-mno-red-zone");
					model = "-mcmodel=kernel";
					nolibc = 1;
					break;
				}
				error(arg);
				break;
#endif	/* __x86 */
			case 'O':
				if (strncmp(arg, "-xO", 3) == 0) {
					size_t len = strlen(arg);
					char *s = NULL;
					int c = *(arg + 3);
					int level;

					if (len != 4 || !isdigit(c))
						error(arg);

					level = atoi(arg + 3);
					if (level > 5)
						error(arg);
					if (level >= 2) {
						/*
						 * For gcc-3.4.x at -O2 we
						 * need to disable optimizations
						 * that break ON.
						 */
						optim_disable(ctx->i_ae, level);
						/*
						 * limit -xO3 to -O2 as well.
						 */
						level = 2;
					}
					if (asprintf(&s, "-O%d", level) == -1)
						nomem();
					newae(ctx->i_ae, s);
					free(s);
					break;
				}
				error(arg);
				break;
			case 't':
				if (strncmp(arg, "-xtarget=", 9) == 0) {
					xlate(ctx->i_ae, arg + 9, xtarget_tbl);
					break;
				}
				error(arg);
				break;
			default:
				error(arg);
				break;
			}
			break;
		case 'Y':
			if (arglen == 1) {
				if ((arg = *++ctx->i_oldargv) == NULL ||
				    *arg == '\0')
					error("-Y");
				ctx->i_oldargc--;
				arglen = strlen(arg + 1);
			} else {
				arg += 2;
			}
			if (strncmp(arg, "I,", 2) == 0) {
				char *s = strdup(arg);
				s[0] = '-';
				s[1] = 'I';
				newae(ctx->i_ae, "-nostdinc");
				newae(ctx->i_ae, s);
				free(s);
				break;
			}
			error(arg);
			break;
		default:
			error(arg);
			break;
		}
	}

	free(nameflag);

	/*
	 * When compiling multiple source files in a single invocation some
	 * compilers output objects into the current directory with
	 * predictable and conventional names.
	 *
	 * We prevent any attempt to compile multiple files at once so that
	 * any such objects created by a shadow can't escape into a later
	 * link-edit.
	 */
	if (c_files > 1 && op != CW_O_PREPROCESS) {
		errx(2, "multiple source files are "
		    "allowed only with -E or -P");
	}

	/*
	 * Make sure that we do not have any unintended interactions between
	 * the xarch options passed in and the version of the Studio compiler
	 * used.
	 */
	if ((mflag & (SS11|SS12)) == (SS11|SS12)) {
		errx(2,
		    "Conflicting \"-xarch=\" flags (both Studio 11 and 12)\n");
	}

	switch (mflag) {
	case 0:
	case M32:
	case M64:
	case SS12:
	case SS11:
	case (SS11|M32):
	case (SS11|M64):
	case (SS12|M32):
	case (SS12|M64):
		break;
	default:
		(void) fprintf(stderr,
		    "Incompatible -xarch= and/or -m32/-m64 options used.\n");
		exit(2);
	}

	if (ctx->i_flags & CW_F_SHADOW) {
		if (op == CW_O_PREPROCESS)
			exit(0);
		else if (op == CW_O_LINK && c_files == 0)
			exit(0);
	}

	if (model != NULL)
		newae(ctx->i_ae, model);
	if (!nolibc)
		newae(ctx->i_ae, "-lc");
	if (!seen_o && (ctx->i_flags & CW_F_SHADOW)) {
		newae(ctx->i_ae, "-o");
		newae(ctx->i_ae, discard_file_name(ctx, NULL));
	}
}

static void
do_smatch(cw_ictx_t *ctx)
{
	if (ctx->i_flags & CW_F_PROG) {
		newae(ctx->i_ae, "--version");
		return;
	}

	/*
	 * Some sources shouldn't run smatch at all.
	 */
	for (int i = 0; i < ctx->i_oldargc; i++) {
		char *arg = ctx->i_oldargv[i];

		if (strcmp(arg, "-_smatch=off") == 0) {
			ctx->i_flags &= ~(CW_F_EXEC | CW_F_ECHO);
			return;
		}

		/* smatch can't handle asm */
		if ((arg[0] != '-') && is_asm_file(arg)) {
			ctx->i_flags &= ~(CW_F_EXEC | CW_F_ECHO);
			return;
		}
	}

	/*
	 * smatch can handle gcc's options.
	 */
	do_gcc(ctx);
}

static void
do_cc(cw_ictx_t *ctx)
{
	int in_output = 0, seen_o = 0, c_files = 0;
	cw_op_t op = CW_O_LINK;
	char *nameflag;

	if (ctx->i_flags & CW_F_PROG) {
		newae(ctx->i_ae, "-V");
		return;
	}

	if (asprintf(&nameflag, "-_%s=", ctx->i_compiler->c_name) == -1)
		nomem();

	while (--ctx->i_oldargc > 0) {
		char *arg = *++ctx->i_oldargv;

		if (strncmp(arg, "-_CC=", 5) == 0) {
			newae(ctx->i_ae, strchr(arg, '=') + 1);
			continue;
		}

		if (*arg != '-') {
			if (!in_output && is_source_file(arg))
				c_files++;

			if (in_output == 0 || !(ctx->i_flags & CW_F_SHADOW)) {
				newae(ctx->i_ae, arg);
			} else {
				in_output = 0;
				newae(ctx->i_ae, discard_file_name(ctx, arg));
			}
			continue;
		}
		switch (*(arg + 1)) {
		case '_':
			if ((strncmp(arg, nameflag, strlen(nameflag)) == 0) ||
			    (strncmp(arg, "-_cc=", 5) == 0) ||
			    (strncmp(arg, "-_sun=", 6) == 0)) {
				newae(ctx->i_ae, strchr(arg, '=') + 1);
			}
			break;

		case 'V':
			ctx->i_flags &= ~CW_F_ECHO;
			newae(ctx->i_ae, arg);
			break;
		case 'o':
			seen_o = 1;
			if (strlen(arg) == 2) {
				in_output = 1;
				newae(ctx->i_ae, arg);
			} else if (ctx->i_flags & CW_F_SHADOW) {
				newae(ctx->i_ae, "-o");
				newae(ctx->i_ae, discard_file_name(ctx, arg));
			} else {
				newae(ctx->i_ae, arg);
			}
			break;
		case 'c':
		case 'S':
			if (strlen(arg) == 2)
				op = CW_O_COMPILE;
			newae(ctx->i_ae, arg);
			break;
		case 'E':
		case 'P':
			if (strlen(arg) == 2)
				op = CW_O_PREPROCESS;
		/*FALLTHROUGH*/
		default:
			newae(ctx->i_ae, arg);
		}
	}

	free(nameflag);

	/* See the comment on this same code in do_gcc() */
	if (c_files > 1 && op != CW_O_PREPROCESS) {
		errx(2, "multiple source files are "
		    "allowed only with -E or -P");
	}

	if (ctx->i_flags & CW_F_SHADOW) {
		if (op == CW_O_PREPROCESS)
			exit(0);
		else if (op == CW_O_LINK && c_files == 0)
			exit(0);
	}

	if (!seen_o && (ctx->i_flags & CW_F_SHADOW)) {
		newae(ctx->i_ae, "-o");
		newae(ctx->i_ae, discard_file_name(ctx, NULL));
	}
}

static void
prepctx(cw_ictx_t *ctx)
{
	newae(ctx->i_ae, ctx->i_compiler->c_path);

	if (ctx->i_flags & CW_F_PROG) {
		(void) printf("%s: %s\n", (ctx->i_flags & CW_F_SHADOW) ?
		    "shadow" : "primary", ctx->i_compiler->c_path);
		(void) fflush(stdout);
	}

	/*
	 * If LD_ALTEXEC is already set, the expectation would be that that
	 * link-editor is run, as such we need to leave it the environment
	 * alone and let that happen.
	 */
	if ((ctx->i_linker != NULL) && (getenv("LD_ALTEXEC") == NULL))
		setenv("LD_ALTEXEC", ctx->i_linker, 1);

	if (!(ctx->i_flags & CW_F_XLATE))
		return;

	switch (ctx->i_compiler->c_style) {
	case SUN:
		do_cc(ctx);
		break;
	case GNU:
		do_gcc(ctx);
		break;
	case SMATCH:
		do_smatch(ctx);
		break;
	}
}

static int
invoke(cw_ictx_t *ctx)
{
	char **newargv, *makeflags;
	int ac;
	struct ae *a;

	newargv = calloc(ctx->i_ae->ael_argc + 1, sizeof (*newargv));
	if (newargv == NULL)
		nomem();

	/*
	 * Check to see if the silent make flag is present (-s), if so, do not
	 * echo. The MAKEFLAGS environment variable is set by dmake. By
	 * observation it appears to place short flags without any arguments
	 * first followed by any long form flags or flags with arguments.
	 */
	makeflags = getenv("MAKEFLAGS");
	if (makeflags != NULL) {
		size_t makeflags_len = strlen(makeflags);
		for (size_t i = 0; i < makeflags_len; i++) {
			if (makeflags[i] == 's') {
				ctx->i_flags &= ~CW_F_ECHO;
				break;
			}
			/* end of short flags */
			if (makeflags[i] == ' ')
				break;
		}
	}

	if (ctx->i_flags & CW_F_ECHO)
		(void) fprintf(stderr, "+ ");

	for (ac = 0, a = ctx->i_ae->ael_head; a; a = a->ae_next, ac++) {
		newargv[ac] = a->ae_arg;
		if (ctx->i_flags & CW_F_ECHO)
			(void) fprintf(stderr, "%s ", a->ae_arg);
		if (a == ctx->i_ae->ael_tail)
			break;
	}

	if (ctx->i_flags & CW_F_ECHO) {
		(void) fprintf(stderr, "\n");
		(void) fflush(stderr);
	}

	if (!(ctx->i_flags & CW_F_EXEC))
		return (0);

	/*
	 * We must fix up the environment here so that the dependency files are
	 * not trampled by the shadow compiler. Also take care of GCC
	 * environment variables that will throw off gcc. This assumes a primary
	 * gcc.
	 */
	if ((ctx->i_flags & CW_F_SHADOW) &&
	    (unsetenv("SUNPRO_DEPENDENCIES") != 0 ||
	    unsetenv("DEPENDENCIES_OUTPUT") != 0 ||
	    unsetenv("GCC_ROOT") != 0)) {
		(void) fprintf(stderr, "error: environment setup failed: %s\n",
		    strerror(errno));
		return (-1);
	}

	(void) execv(newargv[0], newargv);
	warn("couldn't run %s", newargv[0]);

	return (-1);
}

static int
reap(cw_ictx_t *ctx)
{
	int status, ret = 0;
	char buf[1024];
	struct stat s;

	/*
	 * Only wait for one specific child.
	 */
	if (ctx->i_pid <= 0)
		return (-1);

	do {
		if (waitpid(ctx->i_pid, &status, 0) < 0) {
			warn("cannot reap child");
			return (-1);
		}
		if (status != 0) {
			if (WIFSIGNALED(status)) {
				ret = -WTERMSIG(status);
				break;
			} else if (WIFEXITED(status)) {
				ret = WEXITSTATUS(status);
				break;
			}
		}
	} while (!WIFEXITED(status) && !WIFSIGNALED(status));

	if (stat(ctx->i_stderr, &s) < 0) {
		warn("stat failed on child cleanup");
		return (-1);
	}
	if (s.st_size != 0) {
		FILE *f;

		if ((f = fopen(ctx->i_stderr, "r")) != NULL) {
			while (fgets(buf, sizeof (buf), f))
				(void) fprintf(stderr, "%s", buf);
			(void) fflush(stderr);
			(void) fclose(f);
		}
	}
	(void) unlink(ctx->i_stderr);
	free(ctx->i_stderr);

	/*
	 * cc returns an error code when given -V; we want that to succeed.
	 */
	if (ctx->i_flags & CW_F_PROG)
		return (0);

	return (ret);
}

static int
exec_ctx(cw_ictx_t *ctx, int block)
{
	if ((ctx->i_stderr = tempnam(ctx->i_tmpdir, "cw")) == NULL) {
		nomem();
		return (-1);
	}

	if ((ctx->i_pid = fork()) == 0) {
		int fd;

		(void) fclose(stderr);
		if ((fd = open(ctx->i_stderr, O_WRONLY | O_CREAT | O_EXCL,
		    0666)) < 0) {
			err(1, "open failed for standard error");
		}
		if (dup2(fd, 2) < 0) {
			err(1, "dup2 failed for standard error");
		}
		if (fd != 2)
			(void) close(fd);
		if (freopen("/dev/fd/2", "w", stderr) == NULL) {
			err(1, "freopen failed for /dev/fd/2");
		}

		prepctx(ctx);
		exit(invoke(ctx));
	}

	if (ctx->i_pid < 0) {
		err(1, "fork failed");
	}

	if (block)
		return (reap(ctx));

	return (0);
}

static void
parse_compiler(const char *spec, cw_compiler_t *compiler)
{
	char *tspec, *token;

	if ((tspec = strdup(spec)) == NULL)
		nomem();

	if ((token = strsep(&tspec, ",")) == NULL)
		errx(1, "Compiler is missing a name: %s", spec);
	compiler->c_name = token;

	if ((token = strsep(&tspec, ",")) == NULL)
		errx(1, "Compiler is missing a path: %s", spec);
	compiler->c_path = token;

	if ((token = strsep(&tspec, ",")) == NULL)
		errx(1, "Compiler is missing a style: %s", spec);

	if ((strcasecmp(token, "gnu") == 0) ||
	    (strcasecmp(token, "gcc") == 0)) {
		compiler->c_style = GNU;
	} else if ((strcasecmp(token, "sun") == 0) ||
	    (strcasecmp(token, "cc") == 0)) {
		compiler->c_style = SUN;
	} else if ((strcasecmp(token, "smatch") == 0)) {
		compiler->c_style = SMATCH;
	} else {
		errx(1, "unknown compiler style: %s", token);
	}

	if (tspec != NULL)
		errx(1, "Excess tokens in compiler: %s", spec);
}

static void
cleanup(cw_ictx_t *ctx)
{
	DIR *dirp;
	struct dirent *dp;
	char buf[MAXPATHLEN];

	if ((dirp = opendir(ctx->i_tmpdir)) == NULL) {
		if (errno != ENOENT) {
			err(1, "couldn't open temp directory: %s",
			    ctx->i_tmpdir);
		} else {
			return;
		}
	}

	errno = 0;
	while ((dp = readdir(dirp)) != NULL) {
		(void) snprintf(buf, MAXPATHLEN, "%s/%s", ctx->i_tmpdir,
		    dp->d_name);

		if (strcmp(dp->d_name, ".") == 0 ||
		    strcmp(dp->d_name, "..") == 0) {
			continue;
		}

		if (unlink(buf) == -1)
			err(1, "failed to unlink temp file: %s", dp->d_name);
		errno = 0;
	}

	if (errno != 0) {
		err(1, "failed to read temporary directory: %s",
		    ctx->i_tmpdir);
	}

	(void) closedir(dirp);
	if (rmdir(ctx->i_tmpdir) != 0) {
		err(1, "failed to unlink temporary directory: %s",
		    ctx->i_tmpdir);
	}
}

int
main(int argc, char **argv)
{
	int ch;
	cw_compiler_t primary = { NULL, NULL, 0 };
	cw_compiler_t shadows[10];
	int nshadows = 0;
	int ret = 0;
	bool do_serial;
	bool do_exec;
	bool vflg = false;
	bool Cflg = false;
	bool cflg = false;
	bool nflg = false;
	char *tmpdir;

	cw_ictx_t *main_ctx;

	static struct option longopts[] = {
		{ "compiler", no_argument, NULL, 'c' },
		{ "linker", required_argument, NULL, 'l' },
		{ "noecho", no_argument, NULL, 'n' },
		{ "primary", required_argument, NULL, 'p' },
		{ "shadow", required_argument, NULL, 's' },
		{ "versions", no_argument, NULL, 'v' },
		{ NULL, 0, NULL, 0 },
	};


	if ((main_ctx = newictx()) == NULL)
		nomem();

	while ((ch = getopt_long(argc, argv, "C", longopts, NULL)) != -1) {
		switch (ch) {
		case 'c':
			cflg = true;
			break;
		case 'C':
			Cflg = true;
			break;
		case 'l':
			if ((main_ctx->i_linker = strdup(optarg)) == NULL)
				nomem();
			break;
		case 'n':
			nflg = true;
			break;
		case 'p':
			if (primary.c_path != NULL) {
				warnx("Only one primary compiler may "
				    "be specified");
				usage();
			}

			parse_compiler(optarg, &primary);
			break;
		case 's':
			if (nshadows >= 10)
				errx(1, "May only use 10 shadows at "
				    "the moment");
			parse_compiler(optarg, &shadows[nshadows]);
			nshadows++;
			break;
		case 'v':
			vflg = true;
			break;
		default:
			(void) fprintf(stderr, "Did you forget '--'?\n");
			usage();
		}
	}

	if (primary.c_path == NULL) {
		warnx("A primary compiler must be specified");
		usage();
	}

	do_serial = getenv("CW_SHADOW_SERIAL") != NULL;
	do_exec = getenv("CW_NO_EXEC") == NULL;

	/* Leave room for argv[0] */
	argc -= (optind - 1);
	argv += (optind - 1);

	main_ctx->i_oldargc = argc;
	main_ctx->i_oldargv = argv;
	main_ctx->i_flags = CW_F_XLATE;
	if (nflg == 0)
		main_ctx->i_flags |= CW_F_ECHO;
	if (do_exec)
		main_ctx->i_flags |= CW_F_EXEC;
	if (Cflg)
		main_ctx->i_flags |= CW_F_CXX;
	main_ctx->i_compiler = &primary;

	if (cflg) {
		(void) fputs(primary.c_path, stdout);
	}

	if (vflg) {
		(void) printf("cw version %s\n", CW_VERSION);
		(void) fflush(stdout);
		main_ctx->i_flags &= ~CW_F_ECHO;
		main_ctx->i_flags |= CW_F_PROG | CW_F_EXEC;
		do_serial = 1;
	}

	tmpdir = getenv("TMPDIR");
	if (tmpdir == NULL)
		tmpdir = "/tmp";

	if (asprintf(&main_ctx->i_tmpdir, "%s/cw.XXXXXX", tmpdir) == -1)
		nomem();

	if ((main_ctx->i_tmpdir = mkdtemp(main_ctx->i_tmpdir)) == NULL)
		errx(1, "failed to create temporary directory");

	ret |= exec_ctx(main_ctx, do_serial);

	for (int i = 0; i < nshadows; i++) {
		int r;
		cw_ictx_t *shadow_ctx;

		if ((shadow_ctx = newictx()) == NULL)
			nomem();

		(void) memcpy(shadow_ctx, main_ctx, sizeof (cw_ictx_t));

		shadow_ctx->i_flags |= CW_F_SHADOW;
		shadow_ctx->i_compiler = &shadows[i];

		r = exec_ctx(shadow_ctx, do_serial);
		if (r == 0) {
			shadow_ctx->i_next = main_ctx->i_next;
			main_ctx->i_next = shadow_ctx;
		}
		ret |= r;
	}

	if (!do_serial) {
		cw_ictx_t *next = main_ctx;
		while (next != NULL) {
			cw_ictx_t *toreap = next;
			next = next->i_next;
			ret |= reap(toreap);
		}
	}

	cleanup(main_ctx);
	return (ret);
}