trunk/src/emul.c

/*
 *  Copyright (C) 2003-2007  Anders Gavare.  All rights reserved.
 *
 *  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. The name of the author may not be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 *
 *
 *  $Id: emul.c,v 1.297 2007/06/15 17:02:37 debug Exp $
 *
 *  Emulation startup and misc. routines.
 */

#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <stdarg.h>
#include <string.h>
#include <unistd.h>

#include "arcbios.h"
#include "cpu.h"
#include "emul.h"
#include "console.h"
#include "debugger.h"
#include "device.h"
#include "diskimage.h"
#include "exec_elf.h"
#include "machine.h"
#include "memory.h"
#include "mips_cpu_types.h"
#include "misc.h"
#include "net.h"
#include "settings.h"
#include "timer.h"
#include "useremul.h"
#include "x11.h"


extern int extra_argc;
extern char **extra_argv;

extern int verbose;
extern int quiet_mode;
extern int force_debugger_at_exit;
extern int single_step;
extern int old_show_trace_tree;
extern int old_instruction_trace;
extern int old_quiet_mode;
extern int quiet_mode;
extern int native_code_translation_enabled;


/*
 *  add_breakpoints():
 *
 *  Take the strings breakpoint_string[] and convert to addresses
 *  (and store them in breakpoint_addr[]).
 *
 *  TODO: This function should be moved elsewhere.
 */
static void add_breakpoints(struct machine *m)
{
        int i;
        int string_flag;
        uint64_t dp;

        for (i=0; i<m->breakpoints.n; i++) {
                string_flag = 0;
                dp = strtoull(m->breakpoints.string[i], NULL, 0);

                /*
                 *  If conversion resulted in 0, then perhaps it is a
                 *  symbol:
                 */
                if (dp == 0) {
                        uint64_t addr;
                        int res = get_symbol_addr(&m->symbol_context,
                            m->breakpoints.string[i], &addr);
                        if (!res) {
                                fprintf(stderr,
                                    "ERROR! Breakpoint '%s' could not be"
                                        " parsed\n",
                                    m->breakpoints.string[i]);
                                exit(1);
                        } else {
                                dp = addr;
                                string_flag = 1;
                        }
                }

                /*
                 *  TODO:  It would be nice if things like   symbolname+0x1234
                 *  were automatically converted into the correct address.
                 */

                if (m->arch == ARCH_MIPS) {
                        if ((dp >> 32) == 0 && ((dp >> 31) & 1))
                                dp |= 0xffffffff00000000ULL;
                }

                m->breakpoints.addr[i] = dp;

                debug("breakpoint %i: 0x%llx", i, (long long)dp);
                if (string_flag)
                        debug(" (%s)", m->breakpoints.string[i]);
                debug("\n");
        }
}


/*
 *  fix_console():
 */
static void fix_console(void)
{
        console_deinit_main();
}


/*
 *  emul_new():
 *
 *  Returns a reasonably initialized struct emul.
 */
struct emul *emul_new(char *name, int id)
{
        struct emul *e;

        CHECK_ALLOCATION(e = malloc(sizeof(struct emul)));
        memset(e, 0, sizeof(struct emul));

        CHECK_ALLOCATION(e->path = malloc(15));
        snprintf(e->path, 15, "emul[%i]", id);

        e->settings = settings_new();

        settings_add(e->settings, "n_machines", 0,
            SETTINGS_TYPE_INT, SETTINGS_FORMAT_DECIMAL,
            (void *) &e->n_machines);

        /*  TODO: More settings?  */

        /*  Sane default values:  */
        e->n_machines = 0;
        e->next_serial_nr = 1;

        if (name != NULL) {
                CHECK_ALLOCATION(e->name = strdup(name));
                settings_add(e->settings, "name", 0,
                    SETTINGS_TYPE_STRING, SETTINGS_FORMAT_STRING,
                    (void *) &e->name);
        }

        return e;
}


/*
 *  emul_destroy():
 *
 *  Destroys a previously created emul object.
 */
void emul_destroy(struct emul *emul)
{
        int i;

        if (emul->name != NULL) {
                settings_remove(emul->settings, "name");
                free(emul->name);
        }

        for (i=0; i<emul->n_machines; i++)
                machine_destroy(emul->machines[i]);

        if (emul->machines != NULL)
                free(emul->machines);

        /*  Remove any remaining level-1 settings:  */
        settings_remove_all(emul->settings);
        settings_destroy(emul->settings);

        free(emul);
}


/*
 *  emul_add_machine():
 *
 *  Calls machine_new(), adds the new machine into the emul struct, and
 *  returns a pointer to the new machine.
 *
 *  This function should be used instead of manually calling machine_new().
 */
struct machine *emul_add_machine(struct emul *e, char *name)
{
        struct machine *m;
        char tmpstr[20];
        int i;

        m = machine_new(name, e, e->n_machines);
        m->serial_nr = (e->next_serial_nr ++);

        i = e->n_machines ++;

        CHECK_ALLOCATION(e->machines = realloc(e->machines,
            sizeof(struct machine *) * e->n_machines));

        e->machines[i] = m;

        snprintf(tmpstr, sizeof(tmpstr), "machine[%i]", i);
        settings_add(e->settings, tmpstr, 1, SETTINGS_TYPE_SUBSETTINGS, 0,
            e->machines[i]->settings);

        return m;
}


/*
 *  add_arc_components():
 *
 *  This function adds ARCBIOS memory descriptors for the loaded program,
 *  and ARCBIOS components for SCSI devices.
 */
static void add_arc_components(struct machine *m)
{
        struct cpu *cpu = m->cpus[m->bootstrap_cpu];
        uint64_t start = cpu->pc & 0x1fffffff;
        uint64_t len = 0xc00000 - start;
        struct diskimage *d;
        uint64_t scsicontroller, scsidevice, scsidisk;

        if ((cpu->pc >> 60) != 0xf) {
                start = cpu->pc & 0xffffffffffULL;
                len = 0xc00000 - start;
        }

        len += 1048576 * m->memory_offset_in_mb;

        /*
         *  NOTE/TODO: magic 12MB end of load program area
         *
         *  Hm. This breaks the old FreeBSD/MIPS snapshots...
         */
#if 0
        arcbios_add_memory_descriptor(cpu,
            0x60000 + m->memory_offset_in_mb * 1048576,
            start-0x60000 - m->memory_offset_in_mb * 1048576,
            ARCBIOS_MEM_FreeMemory);
#endif
        arcbios_add_memory_descriptor(cpu,
            start, len, ARCBIOS_MEM_LoadedProgram);

        scsicontroller = arcbios_get_scsicontroller(m);
        if (scsicontroller == 0)
                return;

        /*  TODO: The device 'name' should defined be somewhere else.  */

        d = m->first_diskimage;
        while (d != NULL) {
                if (d->type == DISKIMAGE_SCSI) {
                        int a, b, flags = COMPONENT_FLAG_Input;
                        char component_string[100];
                        char *name = "DEC     RZ58     (C) DEC2000";

                        /*  Read-write, or read-only?  */
                        if (d->writable)
                                flags |= COMPONENT_FLAG_Output;
                        else
                                flags |= COMPONENT_FLAG_ReadOnly;

                        a = COMPONENT_TYPE_DiskController;
                        b = COMPONENT_TYPE_DiskPeripheral;

                        if (d->is_a_cdrom) {
                                flags |= COMPONENT_FLAG_Removable;
                                a = COMPONENT_TYPE_CDROMController;
                                b = COMPONENT_TYPE_FloppyDiskPeripheral;
                                name = "NEC     CD-ROM CDR-210P 1.0 ";
                        }

                        scsidevice = arcbios_addchild_manual(cpu,
                            COMPONENT_CLASS_ControllerClass,
                            a, flags, 1, 2, d->id, 0xffffffff,
                            name, scsicontroller, NULL, 0);

                        scsidisk = arcbios_addchild_manual(cpu,
                            COMPONENT_CLASS_PeripheralClass,
                            b, flags, 1, 2, 0, 0xffffffff, NULL,
                            scsidevice, NULL, 0);

                        /*
                         *  Add device string to component address mappings:
                         *  "scsi(0)disk(0)rdisk(0)partition(0)"
                         */

                        if (d->is_a_cdrom) {
                                snprintf(component_string,
                                    sizeof(component_string),
                                    "scsi(0)cdrom(%i)", d->id);
                                arcbios_add_string_to_component(m,
                                    component_string, scsidevice);

                                snprintf(component_string,
                                    sizeof(component_string),
                                    "scsi(0)cdrom(%i)fdisk(0)", d->id);
                                arcbios_add_string_to_component(m,
                                    component_string, scsidisk);
                        } else {
                                snprintf(component_string,
                                    sizeof(component_string),
                                    "scsi(0)disk(%i)", d->id);
                                arcbios_add_string_to_component(m,
                                    component_string, scsidevice);

                                snprintf(component_string,
                                    sizeof(component_string),
                                    "scsi(0)disk(%i)rdisk(0)", d->id);
                                arcbios_add_string_to_component(m,
                                    component_string, scsidisk);
                        }
                }

                d = d->next;
        }
}


/*
 *  emul_machine_setup():
 *
 *      o)  Initialize the hardware (RAM, devices, CPUs, ...) which
 *          will be emulated in this machine.
 *
 *      o)  Load ROM code and/or other programs into emulated memory.
 *
 *      o)  Special hacks needed after programs have been loaded.
 */
void emul_machine_setup(struct machine *m, int n_load, char **load_names,
        int n_devices, char **device_names)
{
        struct cpu *cpu;
        int i, iadd = DEBUG_INDENTATION;
        uint64_t memory_amount, entrypoint = 0, gp = 0, toc = 0;
        int byte_order;

        debug("machine \"%s\":\n", m->name);
        debug_indentation(iadd);

        /*  For userland-only, this decides which ARCH/cpu_name to use:  */
        if (m->machine_type == MACHINE_USERLAND && m->userland_emul != NULL) {
                useremul_name_to_useremul(NULL, m->userland_emul,
                    &m->arch, &m->machine_name, &m->cpu_name);
                if (m->arch == ARCH_NOARCH) {
                        printf("Unsupported userland emulation mode.\n");
                        exit(1);
                }
        }

        if (m->machine_type == MACHINE_NONE) {
                fatal("No machine type specified?\n");
                exit(1);
        }

        m->cpu_family = cpu_family_ptr_by_number(m->arch);

        if (m->arch == ARCH_ALPHA)
                m->arch_pagesize = 8192;

        machine_memsize_fix(m);

        /*
         *  Create the system's memory:
         *
         *  (Don't print the amount for userland-only emulation; the
         *  size doesn't matter.)
         */
        if (m->machine_type != MACHINE_USERLAND)
                debug("memory: %i MB", m->physical_ram_in_mb);
        memory_amount = (uint64_t)m->physical_ram_in_mb * 1048576;
        if (m->memory_offset_in_mb > 0) {
                /*
                 *  A special hack is used for some SGI models,
                 *  where memory is offset by 128MB to leave room for
                 *  EISA space and other things.
                 */
                debug(" (offset by %iMB)", m->memory_offset_in_mb);
                memory_amount += 1048576 * m->memory_offset_in_mb;
        }
        m->memory = memory_new(memory_amount, m->arch);
        if (m->machine_type != MACHINE_USERLAND)
                debug("\n");

        /*  Create CPUs:  */
        if (m->cpu_name == NULL)
                machine_default_cputype(m);
        if (m->ncpus == 0) {
                /*  TODO: This should be moved elsewhere...  */
                if (m->machine_type == MACHINE_BEBOX)
                        m->ncpus = 2;
                else
                        m->ncpus = 1;
        }

        CHECK_ALLOCATION(m->cpus = malloc(sizeof(struct cpu *) * m->ncpus));
        memset(m->cpus, 0, sizeof(struct cpu *) * m->ncpus);

        debug("cpu0");
        if (m->ncpus > 1)
                debug(" .. cpu%i", m->ncpus - 1);
        debug(": ");
        for (i=0; i<m->ncpus; i++) {
                m->cpus[i] = cpu_new(m->memory, m, i, m->cpu_name);
                if (m->cpus[i] == NULL) {
                        fprintf(stderr, "Unable to create CPU object. "
                            "Aborting.");
                        exit(1);
                }
        }
        debug("\n");

        if (m->use_random_bootstrap_cpu)
                m->bootstrap_cpu = random() % m->ncpus;
        else
                m->bootstrap_cpu = 0;

        cpu = m->cpus[m->bootstrap_cpu];

        /*  Set cpu->useremul_syscall, and use userland_memory_rw:  */
        if (m->userland_emul != NULL) {
                useremul_name_to_useremul(cpu,
                    m->userland_emul, NULL, NULL, NULL);

                switch (m->arch) {

                case ARCH_ALPHA:
                        cpu->memory_rw = alpha_userland_memory_rw;
                        break;

                default:
                        cpu->memory_rw = userland_memory_rw;
                }
        }

        if (m->x11_md.in_use)
                x11_init(m);

        /*  Fill memory with random bytes:  */
        if (m->random_mem_contents) {
                for (i=0; i<m->physical_ram_in_mb * 1048576; i+=256) {
                        unsigned char data[256];
                        unsigned int j;
                        for (j=0; j<sizeof(data); j++)
                                data[j] = random() & 255;
                        cpu->memory_rw(cpu, m->memory, i, data, sizeof(data),
                            MEM_WRITE, CACHE_NONE | NO_EXCEPTIONS | PHYSICAL);
                }
        }

        if (m->userland_emul != NULL) {
                /*
                 *  For userland-only emulation, no machine emulation
                 *  is needed.
                 */
        } else {
                for (i=0; i<n_devices; i++)
                        device_add(m, device_names[i]);

                machine_setup(m);
        }

        diskimage_dump_info(m);
        console_debug_dump(m);

        /*  Load files (ROM code, boot code, ...) into memory:  */
        if (n_load == 0) {
                if (m->first_diskimage != NULL) {
                        if (!load_bootblock(m, cpu, &n_load, &load_names)) {
                                fprintf(stderr, "\nNo executable files were"
                                    " specified, and booting directly from disk"
                                    " failed.\n");
                                exit(1);
                        }
                } else {
                        fprintf(stderr, "No executable file(s) loaded, and "
                            "we are not booting directly from a disk image."
                            "\nAborting.\n");
                        exit(1);
                }
        }

        while (n_load > 0) {
                FILE *tmp_f;
                char *name_to_load = *load_names;
                int remove_after_load = 0;

                /*  Special hack for removing temporary files:  */
                if (name_to_load[0] == 8) {
                        name_to_load ++;
                        remove_after_load = 1;
                }

                /*
                 *  gzipped files are automagically gunzipped:
                 *  NOTE/TODO: This isn't secure. system() is used.
                 */
                tmp_f = fopen(name_to_load, "r");
                if (tmp_f != NULL) {
                        unsigned char buf[2];           /*  gzip header  */
                        memset(buf, 0, sizeof(buf));
                        fread(buf, 1, sizeof(buf), tmp_f);
                        if (buf[0]==0x1f && buf[1]==0x8b) {
                                size_t zzlen = strlen(name_to_load)*2 + 100;
                                char *zz;

                                CHECK_ALLOCATION(zz = malloc(zzlen));
                                debug("gunziping %s\n", name_to_load);

                                /*
                                 *  gzip header found.  If this was a file
                                 *  extracted from, say, a CDROM image, then it
                                 *  already has a temporary name. Otherwise we
                                 *  have to gunzip into a temporary file.
                                 */
                                if (remove_after_load) {
                                        snprintf(zz, zzlen, "mv %s %s.gz",
                                            name_to_load, name_to_load);
                                        system(zz);
                                        snprintf(zz, zzlen, "gunzip %s.gz",
                                            name_to_load);
                                        system(zz);
                                } else {
                                        /*  gunzip into new temp file:  */
                                        int tmpfile_handle;
                                        char *new_temp_name;
                                        CHECK_ALLOCATION(new_temp_name =
                                            strdup("/tmp/gxemul.XXXXXXXXXXXX"));
                                        tmpfile_handle = mkstemp(new_temp_name);
                                        close(tmpfile_handle);
                                        snprintf(zz, zzlen, "gunzip -c '%s' > "
                                            "%s", name_to_load, new_temp_name);
                                        system(zz);
                                        name_to_load = new_temp_name;
                                        remove_after_load = 1;
                                }
                                free(zz);
                        }
                        fclose(tmp_f);
                }

                byte_order = NO_BYTE_ORDER_OVERRIDE;

                /*
                 *  Load the file:  :-)
                 */
                file_load(m, m->memory, name_to_load, &entrypoint,
                    m->arch, &gp, &byte_order, &toc);

                if (remove_after_load) {
                        debug("removing %s\n", name_to_load);
                        unlink(name_to_load);
                }

                if (byte_order != NO_BYTE_ORDER_OVERRIDE)
                        cpu->byte_order = byte_order;

                cpu->pc = entrypoint;

                switch (m->arch) {

                case ARCH_ALPHA:
                        /*  For position-independent code:  */
                        cpu->cd.alpha.r[ALPHA_T12] = cpu->pc;
                        break;

                case ARCH_ARM:
                        if (cpu->pc & 3) {
                                fatal("ARM: lowest bits of pc set: TODO\n");
                                exit(1);
                        }
                        cpu->pc &= 0xfffffffc;
                        break;

                case ARCH_M88K:
                        if (cpu->pc & 3) {
                                fatal("M88K: lowest bits of pc set: TODO\n");
                                exit(1);
                        }
                        cpu->pc &= 0xfffffffc;
                        break;

                case ARCH_MIPS:
                        if ((cpu->pc >> 32) == 0 && (cpu->pc & 0x80000000ULL))
                                cpu->pc |= 0xffffffff00000000ULL;

                        cpu->cd.mips.gpr[MIPS_GPR_GP] = gp;

                        if ((cpu->cd.mips.gpr[MIPS_GPR_GP] >> 32) == 0 &&
                            (cpu->cd.mips.gpr[MIPS_GPR_GP] & 0x80000000ULL))
                                cpu->cd.mips.gpr[MIPS_GPR_GP] |=
                                    0xffffffff00000000ULL;
                        break;

                case ARCH_PPC:
                        /*  See http://www.linuxbase.org/spec/ELF/ppc64/
                            spec/x458.html for more info.  */
                        cpu->cd.ppc.gpr[2] = toc;
                        /*  TODO  */
                        if (cpu->cd.ppc.bits == 32)
                                cpu->pc &= 0xffffffffULL;
                        break;

                case ARCH_SH:
                        if (cpu->cd.sh.cpu_type.bits == 32)
                                cpu->pc &= 0xffffffffULL;
                        cpu->pc &= ~1;
                        break;

                case ARCH_SPARC:
                        break;

                default:
                        fatal("emul_machine_setup(): Internal error: "
                            "Unimplemented arch %i\n", m->arch);
                        exit(1);
                }

                /*
                 *  For userland emulation, the remaining items
                 *  on the command line will be passed as parameters
                 *  to the emulated program, and will not be treated
                 *  as filenames to load into the emulator.
                 *  The program's name will be in load_names[0], and the
                 *  rest of the parameters in load_names[1] and up.
                 */
                if (m->userland_emul != NULL)
                        break;

                n_load --;
                load_names ++;
        }

        if (m->byte_order_override != NO_BYTE_ORDER_OVERRIDE)
                cpu->byte_order = m->byte_order_override;

        /*  Same byte order and entrypoint for all CPUs:  */
        for (i=0; i<m->ncpus; i++)
                if (i != m->bootstrap_cpu) {
                        m->cpus[i]->byte_order = cpu->byte_order;
                        m->cpus[i]->pc = cpu->pc;
                }

        if (m->userland_emul != NULL)
                useremul_setup(cpu, n_load, load_names);

        /*  Startup the bootstrap CPU:  */
        cpu->running = 1;

        /*  ... or pause all CPUs, if start_paused is set:  */
        if (m->start_paused) {
                for (i=0; i<m->ncpus; i++)
                        m->cpus[i]->running = 0;
        }

        /*  Parse and add breakpoints:  */
        add_breakpoints(m);

        /*  TODO: This is MIPS-specific!  */
        if (m->machine_type == MACHINE_PMAX &&
            cpu->cd.mips.cpu_type.mmu_model == MMU3K)
                add_symbol_name(&m->symbol_context,
                    0x9fff0000, 0x10000, "r2k3k_cache", 0, 0);

        symbol_recalc_sizes(&m->symbol_context);

        /*  Special hack for ARC/SGI emulation:  */
        if ((m->machine_type == MACHINE_ARC ||
            m->machine_type == MACHINE_SGI) && m->prom_emulation)
                add_arc_components(m);

        debug("starting cpu%i at ", m->bootstrap_cpu);
        switch (m->arch) {

        case ARCH_ARM:
                /*  ARM cpus aren't 64-bit:  */
                debug("0x%08"PRIx32, (uint32_t) entrypoint);
                break;

        case ARCH_MIPS:
                if (cpu->is_32bit) {
                        debug("0x%08"PRIx32, (uint32_t)
                            m->cpus[m->bootstrap_cpu]->pc);
                        if (cpu->cd.mips.gpr[MIPS_GPR_GP] != 0)
                                debug(" (gp=0x%08"PRIx32")", (uint32_t)
                                    m->cpus[m->bootstrap_cpu]->cd.mips.gpr[
                                    MIPS_GPR_GP]);
                } else {
                        debug("0x%016"PRIx64, (uint64_t)
                            m->cpus[m->bootstrap_cpu]->pc);
                        if (cpu->cd.mips.gpr[MIPS_GPR_GP] != 0)
                                debug(" (gp=0x%016"PRIx64")", (uint64_t)
                                    cpu->cd.mips.gpr[MIPS_GPR_GP]);
                }
                break;

        case ARCH_PPC:
                if (cpu->cd.ppc.bits == 32)
                        debug("0x%08"PRIx32, (uint32_t) entrypoint);
                else
                        debug("0x%016"PRIx64, (uint64_t) entrypoint);
                break;

        default:
                if (cpu->is_32bit)
                        debug("0x%08"PRIx32, (uint32_t) cpu->pc);
                else
                        debug("0x%016"PRIx64, (uint64_t) cpu->pc);
        }
        debug("\n");

        debug_indentation(-iadd);
}


/*
 *  emul_dumpinfo():
 *
 *  Dump info about all machines in an emul.
 */
void emul_dumpinfo(struct emul *e)
{
        int j, nm, iadd = DEBUG_INDENTATION;

        if (e->net != NULL)
                net_dumpinfo(e->net);

        nm = e->n_machines;
        for (j=0; j<nm; j++) {
                debug("machine %i: \"%s\"\n", j, e->machines[j]->name);
                debug_indentation(iadd);
                machine_dumpinfo(e->machines[j]);
                debug_indentation(-iadd);
        }
}


/*
 *  emul_simple_init():
 *
 *  For a normal setup:
 *
 *      o)  Initialize a network.
 *      o)  Initialize one machine.
 *
 *  For a userland-only setup:
 *
 *      o)  Initialize a "pseudo"-machine.
 */
void emul_simple_init(struct emul *emul)
{
        int iadd = DEBUG_INDENTATION;
        struct machine *m;

        if (emul->n_machines != 1) {
                fprintf(stderr, "emul_simple_init(): n_machines != 1\n");
                exit(1);
        }

        m = emul->machines[0];

        if (m->userland_emul == NULL) {
                debug("Simple setup...\n");
                debug_indentation(iadd);

                /*  Create a simple network:  */
                emul->net = net_init(emul, NET_INIT_FLAG_GATEWAY,
                    NET_DEFAULT_IPV4_MASK,
                    NET_DEFAULT_IPV4_LEN,
                    NULL, 0, 0, NULL);
        } else {
                /*  Userland pseudo-machine:  */
                debug("Syscall emulation (userland-only) setup...\n");
                debug_indentation(iadd);
        }

        /*  Create the machine:  */
        emul_machine_setup(m, extra_argc, extra_argv, 0, NULL);

        debug_indentation(-iadd);
}


/*
 *  emul_create_from_configfile():
 *
 *  Create an emul struct by reading settings from a configuration file.
 */
struct emul *emul_create_from_configfile(char *fname, int id)
{
        int iadd = DEBUG_INDENTATION;
        struct emul *e = emul_new(fname, id);

        debug("Creating emulation from configfile \"%s\":\n", fname);
        debug_indentation(iadd);

        emul_parse_config(e, fname);

        debug_indentation(-iadd);
        return e;
}


/*
 *  emul_run():
 *
 *      o)  Set up things needed before running emulations.
 *
 *      o)  Run emulations (one or more, in parallel).
 *
 *      o)  De-initialize things.
 */
void emul_run(struct emul **emuls, int n_emuls)
{
        struct emul *e;
        int i = 0, j, go = 1, n, anything;

        if (n_emuls < 1) {
                fprintf(stderr, "emul_run(): no thing to do\n");
                return;
        }

        atexit(fix_console);

        /*  Initialize the interactive debugger:  */
        debugger_init(emuls, n_emuls);

        /*  Run any additional debugger commands before starting:  */
        for (i=0; i<n_emuls; i++) {
                struct emul *emul = emuls[i];
                if (emul->n_debugger_cmds > 0) {
                        int j;
                        if (i == 0)
                                print_separator_line();
                        for (j = 0; j < emul->n_debugger_cmds; j ++) {
                                debug("> %s\n", emul->debugger_cmds[j]);
                                debugger_execute_cmd(emul->debugger_cmds[j],
                                    strlen(emul->debugger_cmds[j]));
                        }
                }
        }

        print_separator_line();
        debug("\n");


        /*
         *  console_init_main() makes sure that the terminal is in a
         *  reasonable state.
         *
         *  The SIGINT handler is for CTRL-C  (enter the interactive debugger).
         *
         *  The SIGCONT handler is invoked whenever the user presses CTRL-Z
         *  (or sends SIGSTOP) and then continues. It makes sure that the
         *  terminal is in an expected state.
         */
        console_init_main(emuls[0]);    /*  TODO: what is a good argument?  */
        signal(SIGINT, debugger_activate);
        signal(SIGCONT, console_sigcont);

        /*  Not in verbose mode? Then set quiet_mode.  */
        if (!verbose)
                quiet_mode = 1;

        /*  Initialize all CPUs in all machines in all emulations:  */
        for (i=0; i<n_emuls; i++) {
                e = emuls[i];
                if (e == NULL)
                        continue;
                for (j=0; j<e->n_machines; j++)
                        cpu_run_init(e->machines[j]);
        }

        /*  TODO: Generalize:  */
        if (emuls[0]->machines[0]->show_trace_tree)
                cpu_functioncall_trace(emuls[0]->machines[0]->cpus[0],
                    emuls[0]->machines[0]->cpus[0]->pc);

        /*  Start emulated clocks:  */
        timer_start();

        /*
         *  MAIN LOOP:
         *
         *  Run all emulations in parallel, running instructions from each
         *  cpu in each machine in each emulation.
         */
        while (go) {
                struct cpu *bootcpu = emuls[0]->machines[0]->cpus[
                    emuls[0]->machines[0]->bootstrap_cpu];

                go = 0;

                /*  Flush X11 and serial console output every now and then:  */
                if (bootcpu->ninstrs > bootcpu->ninstrs_flush + (1<<19)) {
                        x11_check_event(emuls, n_emuls);
                        console_flush();
                        bootcpu->ninstrs_flush = bootcpu->ninstrs;
                }

                if (bootcpu->ninstrs > bootcpu->ninstrs_show + (1<<25)) {
                        bootcpu->ninstrs_since_gettimeofday +=
                            (bootcpu->ninstrs - bootcpu->ninstrs_show);
                        cpu_show_cycles(emuls[0]->machines[0], 0);
                        bootcpu->ninstrs_show = bootcpu->ninstrs;
                }

                if (single_step == ENTER_SINGLE_STEPPING) {
                        /*  TODO: Cleanup!  */
                        old_instruction_trace =
                            emuls[0]->machines[0]->instruction_trace;
                        old_quiet_mode = quiet_mode;
                        old_show_trace_tree =
                            emuls[0]->machines[0]->show_trace_tree;
                        emuls[0]->machines[0]->instruction_trace = 1;
                        emuls[0]->machines[0]->show_trace_tree = 1;
                        quiet_mode = 0;
                        single_step = SINGLE_STEPPING;
                }

                if (single_step == SINGLE_STEPPING)
                        debugger();

                for (i=0; i<n_emuls; i++) {
                        e = emuls[i];

                        for (j=0; j<e->n_machines; j++) {
                                anything = machine_run(e->machines[j]);
                                if (anything)
                                        go = 1;
                        }
                }
        }

        /*  Stop any running timers:  */
        timer_stop();

        /*  Deinitialize all CPUs in all machines in all emulations:  */
        for (i=0; i<n_emuls; i++) {
                e = emuls[i];
                if (e == NULL)
                        continue;
                for (j=0; j<e->n_machines; j++)
                        cpu_run_deinit(e->machines[j]);
        }

        /*  force_debugger_at_exit flag set? Then enter the debugger:  */
        if (force_debugger_at_exit) {
                quiet_mode = 0;
                debugger_reset();
                debugger();
        }

        /*  Any machine using X11? Then wait before exiting:  */
        n = 0;
        for (i=0; i<n_emuls; i++)
                for (j=0; j<emuls[i]->n_machines; j++)
                        if (emuls[i]->machines[j]->x11_md.in_use)
                                n++;
        if (n > 0) {
                printf("Press enter to quit.\n");
                while (!console_charavail(MAIN_CONSOLE)) {
                        x11_check_event(emuls, n_emuls);
                        usleep(10000);
                }
                console_readchar(MAIN_CONSOLE);
        }

        console_deinit_main();
}
