nasm.c

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/* The Netwide Assembler main program module
 *
 * The Netwide Assembler is copyright (C) 1996 Simon Tatham and
 * Julian Hall. All rights reserved. The software is
 * redistributable under the license given in the file "LICENSE"
 * distributed in the NASM archive.
 */

#include "compiler.h"

#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <inttypes.h>
#include <limits.h>
#include <time.h>

#include "nasm.h"
#include "nasmlib.h"
#include "saa.h"
#include "raa.h"
#include "float.h"
#include "stdscan.h"
#include "insns.h"
#include "preproc.h"
#include "parser.h"
#include "eval.h"
#include "assemble.h"
#include "labels.h"
#include "outform.h"
#include "listing.h"

struct forwrefinfo {            /* info held on forward refs. */
    int lineno;
    int operand;
};

static int get_bits(char *value);
static uint32_t get_cpu(char *cpu_str);
static void parse_cmdline(int, char **);
static void assemble_file(char *, StrList **);
static void register_output_formats(void);
static void report_error_gnu(int severity, const char *fmt, ...);
static void report_error_vc(int severity, const char *fmt, ...);
static void report_error_common(int severity, const char *fmt,
                                va_list args);
static bool is_suppressed_warning(int severity);
static void usage(void);
static efunc report_error;

static int using_debug_info, opt_verbose_info;
bool tasm_compatible_mode = false;
int pass0, passn;
int maxbits = 0;
int globalrel = 0;

time_t official_compile_time;

static char inname[FILENAME_MAX];
static char outname[FILENAME_MAX];
static char listname[FILENAME_MAX];
static char errname[FILENAME_MAX];
static int globallineno;        /* for forward-reference tracking */
/* static int pass = 0; */
static struct ofmt *ofmt = NULL;

static FILE *error_file;        /* Where to write error messages */

static FILE *ofile = NULL;
int optimizing = -1;            /* number of optimization passes to take */
static int sb, cmd_sb = 16;     /* by default */
static uint32_t cmd_cpu = IF_PLEVEL;       /* highest level by default */
static uint32_t cpu = IF_PLEVEL;   /* passed to insn_size & assemble.c */
int64_t global_offset_changed;      /* referenced in labels.c */
int64_t prev_offset_changed;
int32_t stall_count;

static struct location location;
int in_abs_seg;                 /* Flag we are in ABSOLUTE seg */
int32_t abs_seg;                   /* ABSOLUTE segment basis */
int32_t abs_offset;                /* ABSOLUTE offset */

static struct RAA *offsets;

static struct SAA *forwrefs;    /* keep track of forward references */
static const struct forwrefinfo *forwref;

static Preproc *preproc;
enum op_type {
    op_normal,                  /* Preprocess and assemble */
    op_preprocess,              /* Preprocess only */
    op_depend,                  /* Generate dependencies */
};
static enum op_type operating_mode;
/* Dependency flags */
static bool depend_emit_phony = false;
static bool depend_missing_ok = false;
static const char *depend_target = NULL;
static const char *depend_file = NULL;

/*
 * Which of the suppressible warnings are suppressed. Entry zero
 * isn't an actual warning, but it used for -w+error/-Werror.
 */

static bool warning_on[ERR_WARN_MAX+1]; /* Current state */
static bool warning_on_global[ERR_WARN_MAX+1]; /* Command-line state */

static const struct warning {
    const char *name;
    const char *help;
    bool enabled;
} warnings[ERR_WARN_MAX+1] = {
    {"error", "treat warnings as errors", false},
    {"macro-params", "macro calls with wrong parameter count", true},
    {"macro-selfref", "cyclic macro references", false},
    {"macro-defaults", "macros with more default than optional parameters", true},
    {"orphan-labels", "labels alone on lines without trailing `:'", true},
    {"number-overflow", "numeric constants does not fit in 64 bits", true},
    {"gnu-elf-extensions", "using 8- or 16-bit relocation in ELF32, a GNU extension", false},
    {"float-overflow", "floating point overflow", true},
    {"float-denorm", "floating point denormal", false},
    {"float-underflow", "floating point underflow", false},
    {"float-toolong", "too many digits in floating-point number", true},
    {"user", "%warning directives", true},
};

/*
 * This is a null preprocessor which just copies lines from input
 * to output. It's used when someone explicitly requests that NASM
 * not preprocess their source file.
 */

static void no_pp_reset(char *, int, efunc, evalfunc, ListGen *, StrList **);
static char *no_pp_getline(void);
static void no_pp_cleanup(int);
static Preproc no_pp = {
    no_pp_reset,
    no_pp_getline,
    no_pp_cleanup
};

/*
 * get/set current offset...
 */
#define GET_CURR_OFFS (in_abs_seg?abs_offset:\
		      raa_read(offsets,location.segment))
#define SET_CURR_OFFS(x) (in_abs_seg?(void)(abs_offset=(x)):\
			 (void)(offsets=raa_write(offsets,location.segment,(x))))

static int want_usage;
static int terminate_after_phase;
int user_nolist = 0;            /* fbk 9/2/00 */

static void nasm_fputs(const char *line, FILE * outfile)
{
    if (outfile) {
        fputs(line, outfile);
        putc('\n', outfile);
    } else
        puts(line);
}

/* Convert a struct tm to a POSIX-style time constant */
static int64_t posix_mktime(struct tm *tm)
{
    int64_t t;
    int64_t y = tm->tm_year;

    /* See IEEE 1003.1:2004, section 4.14 */

    t = (y-70)*365 + (y-69)/4 - (y-1)/100 + (y+299)/400;
    t += tm->tm_yday;
    t *= 24;
    t += tm->tm_hour;
    t *= 60;
    t += tm->tm_min;
    t *= 60;
    t += tm->tm_sec;

    return t;
}

static void define_macros_early(void)
{
    char temp[128];
    struct tm lt, *lt_p, gm, *gm_p;
    int64_t posix_time;

    lt_p = localtime(&official_compile_time);
    if (lt_p) {
	lt = *lt_p;

	strftime(temp, sizeof temp, "__DATE__=\"%Y-%m-%d\"", &lt);
	pp_pre_define(temp);
	strftime(temp, sizeof temp, "__DATE_NUM__=%Y%m%d", &lt);
	pp_pre_define(temp);
	strftime(temp, sizeof temp, "__TIME__=\"%H:%M:%S\"", &lt);
	pp_pre_define(temp);
	strftime(temp, sizeof temp, "__TIME_NUM__=%H%M%S", &lt);
	pp_pre_define(temp);
    }

    gm_p = gmtime(&official_compile_time);
    if (gm_p) {
	gm = *gm_p;

	strftime(temp, sizeof temp, "__UTC_DATE__=\"%Y-%m-%d\"", &gm);
	pp_pre_define(temp);
	strftime(temp, sizeof temp, "__UTC_DATE_NUM__=%Y%m%d", &gm);
	pp_pre_define(temp);
	strftime(temp, sizeof temp, "__UTC_TIME__=\"%H:%M:%S\"", &gm);
	pp_pre_define(temp);
	strftime(temp, sizeof temp, "__UTC_TIME_NUM__=%H%M%S", &gm);
	pp_pre_define(temp);
    }

    if (gm_p)
	posix_time = posix_mktime(&gm);
    else if (lt_p)
	posix_time = posix_mktime(&lt);
    else
	posix_time = 0;

    if (posix_time) {
	snprintf(temp, sizeof temp, "__POSIX_TIME__=%"PRId64, posix_time);
	pp_pre_define(temp);
    }
}

static void define_macros_late(void)
{
    char temp[128];

    snprintf(temp, sizeof(temp), "__OUTPUT_FORMAT__=%s\n",
	     ofmt->shortname);
    pp_pre_define(temp);
}

static void emit_dependencies(StrList *list)
{
    FILE *deps;
    int linepos, len;
    StrList *l, *nl;

    if (depend_file && strcmp(depend_file, "-")) {
	deps = fopen(depend_file, "w");
	if (!deps) {
	    report_error(ERR_NONFATAL|ERR_NOFILE|ERR_USAGE,
			 "unable to write dependency file `%s'", depend_file);
	    return;
	}
    } else {
	deps = stdout;
    }
    
    linepos = fprintf(deps, "%s:", depend_target);
    for (l = list; l; l = l->next) {
	len = strlen(l->str);
	if (linepos + len > 62) {
	    fprintf(deps, " \\\n ");
	    linepos = 1;
	}
	fprintf(deps, " %s", l->str);
	linepos += len+1;
    }
    fprintf(deps, "\n\n");
    
    for (l = list; l; l = nl) {
	if (depend_emit_phony)
	    fprintf(deps, "%s:\n\n", l->str);
	    
	nl = l->next;
	nasm_free(l);
    }

    if (deps != stdout)
	fclose(deps);
}

int main(int argc, char **argv)
{
    StrList *depend_list = NULL, **depend_ptr;

    time(&official_compile_time);

    pass0 = 0;
    want_usage = terminate_after_phase = false;
    report_error = report_error_gnu;

    error_file = stderr;

    tolower_init();

    nasm_set_malloc_error(report_error);
    offsets = raa_init();
    forwrefs = saa_init((int32_t)sizeof(struct forwrefinfo));

    preproc = &nasmpp;
    operating_mode = op_normal;

    seg_init();

    register_output_formats();

    /* Define some macros dependent on the runtime, but not
       on the command line. */
    define_macros_early();

    parse_cmdline(argc, argv);

    if (terminate_after_phase) {
        if (want_usage)
            usage();
        return 1;
    }

    /* If debugging info is disabled, suppress any debug calls */
    if (!using_debug_info)
        ofmt->current_dfmt = &null_debug_form;

    if (ofmt->stdmac)
        pp_extra_stdmac(ofmt->stdmac);
    parser_global_info(ofmt, &location);
    eval_global_info(ofmt, lookup_label, &location);

    /* define some macros dependent of command-line */
    define_macros_late();

    depend_ptr = (depend_file || (operating_mode == op_depend))
	? &depend_list : NULL;
    if (!depend_target)
	depend_target = outname;

    switch (operating_mode) {
    case op_depend:
        {
            char *line;

	    if (depend_missing_ok)
		pp_include_path(NULL);	/* "assume generated" */

            preproc->reset(inname, 0, report_error, evaluate, &nasmlist,
			   depend_ptr);
            if (outname[0] == '\0')
                ofmt->filename(inname, outname, report_error);
            ofile = NULL;
            while ((line = preproc->getline()))
                nasm_free(line);
            preproc->cleanup(0);
        }
        break;

    case op_preprocess:
        {
            char *line;
            char *file_name = NULL;
            int32_t prior_linnum = 0;
            int lineinc = 0;

            if (*outname) {
                ofile = fopen(outname, "w");
                if (!ofile)
                    report_error(ERR_FATAL | ERR_NOFILE,
                                 "unable to open output file `%s'",
                                 outname);
            } else
                ofile = NULL;

            location.known = false;

	    /* pass = 1; */
            preproc->reset(inname, 3, report_error, evaluate, &nasmlist,
			   depend_ptr);

            while ((line = preproc->getline())) {
                /*
                 * We generate %line directives if needed for later programs
                 */
                int32_t linnum = prior_linnum += lineinc;
                int altline = src_get(&linnum, &file_name);
                if (altline) {
                    if (altline == 1 && lineinc == 1)
                        nasm_fputs("", ofile);
                    else {
                        lineinc = (altline != -1 || lineinc != 1);
                        fprintf(ofile ? ofile : stdout,
                                "%%line %"PRId32"+%d %s\n", linnum, lineinc,
                                file_name);
                    }
                    prior_linnum = linnum;
                }
                nasm_fputs(line, ofile);
                nasm_free(line);
            }
            nasm_free(file_name);