/* 
 * (C) Copyright 1992, ..., 2007 the "DOSEMU-Development-Team".
 *
 * for details see file COPYING.DOSEMU in the DOSEMU distribution
 */

/* 
 * Various sundry utilites for dos emulator.
 *
 */
#include "emu.h"

#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <sys/time.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <assert.h>
#include <dlfcn.h>

#include "machcompat.h"
#include "bios.h"
#include "timers.h"
#include "pic.h"
#include "dpmi.h"
#include "debug.h"
#include "utilities.h"
#include "dos2linux.h"
#include "dosemu_config.h"
#ifdef USE_MHPDBG
#include "mhpdbg.h"
#endif

/*
 * NOTE: SHOW_TIME _only_ should be enabled for
 *      internal debugging use, but _never_ for productions releases!
 *      (this would break the port traceing stuff -D+T, which expects
 *      a machine interpretable and compressed format)
 * 
 *                                     --Hans 990213
 */
#define SHOW_TIME	0		/* 0 or 1 */
#ifdef X86_EMULATOR
#include "cpu-emu.h"
#endif

#ifndef INITIAL_LOGBUFSIZE
#define INITIAL_LOGBUFSIZE      0
#endif
#ifndef INITIAL_LOGBUFLIMIT
#define INITIAL_LOGFILELIMIT	(50*1024*1024)
#endif

#ifdef CIRCULAR_LOGBUFFER
#define NUM_CIRC_LINES	32768
#define SIZ_CIRC_LINES	384
#define MAX_LINE_SIZE	(SIZ_CIRC_LINES-16)
char *logbuf;
static char *loglines[NUM_CIRC_LINES];
static int loglineidx = 0;
char *logptr;
#else
#define MAX_LINE_SIZE	1000
static char logbuf_[INITIAL_LOGBUFSIZE+1025];
char *logptr=logbuf_;
char *logbuf=logbuf_;
#endif
int logbuf_size = INITIAL_LOGBUFSIZE;
int logfile_limit = INITIAL_LOGFILELIMIT;
int log_written = 0;

static char hxtab[16]="0123456789abcdef";

static inline char *prhex8 (char *p, unsigned long v)
{
  int i;
  for (i=7; i>=0; --i) { p[i]=hxtab[v&15]; v>>=4; }
  p[8]=' ';
  return p+9;
}

#if SHOW_TIME
static char *timestamp (char *p)
{
  unsigned long t;
  int i;

#ifdef DBG_TIME
  t = GETusTIME(0);
#else
  t = pic_sys_time/1193;
#endif
  /* [12345678]s - SYS time */
    {
      p[0] = '[';
      for (i=8; i>0; --i)
	{ if (t) { p[i]=(t%10)+'0'; t/=10; } else p[i]='0'; }
      p[9]=']'; p[10]=' ';
    }
  return p+11;
}
#else
#define timestamp(p)	(p)
#endif


char *strprintable(char *s)
{
  static char buf[8][128];
  static int bufi = 0;
  char *t, c;

  bufi = (bufi + 1) & 7;
  t = buf[bufi];
  while (*s) {
    c = *s++;
    if ((unsigned)c < ' ') {
      *t++ = '^';
      *t++ = c | 0x40;
    }
    else if ((unsigned)c > 126) {
      *t++ = 'X';
      *t++ = hxtab[(c >> 4) & 15];
      *t++ = hxtab[c & 15];
    }
    else *t++ = c;
  }
  *t++ = 0;
  return buf[bufi];
}

char *chrprintable(char c)
{
  char buf[2];
  buf[0] = c;
  buf[1] = 0;
  return strprintable(buf);
}

int vlog_printf(int flg, const char *fmt, va_list args)
{
  int i;
  static int is_cr = 1;

  if (dosdebug_flags & DBGF_INTERCEPT_LOG) {
    /* we give dosdebug a chance to interrupt on given logoutput */
    i = vmhp_log_intercept(flg, fmt, args);
    if ((dosdebug_flags & DBGF_DISABLE_LOG_TO_FILE) || !dbg_fd) return i;
  }

  if (!flg || !dbg_fd || 
#ifdef USE_MHPDBG
      (shut_debug && (flg<10) && !mhpdbg.active)
#else
      (shut_debug && (flg<10))
#endif
     ) return 0;

#ifdef CIRCULAR_LOGBUFFER
  logptr = loglines[loglineidx++];
#endif
  {
    char *q;

    q = (is_cr? timestamp(logptr) : logptr);
    i = vsnprintf(q, MAX_LINE_SIZE, fmt, args);
    if (i < 0) {	/* truncated for buffer overflow */
      i = MAX_LINE_SIZE-2;
      q[i++]='\n'; q[i]=0; is_cr=1;
    }
    else if (i > 0) is_cr = (q[i-1]=='\n');
    i += (q-logptr);
  }

#ifdef CIRCULAR_LOGBUFFER
  loglineidx %= NUM_CIRC_LINES;
  *(loglines[loglineidx]) = 0;

  if (flg == -1) {
    char *p;
    int i, k;
    k = loglineidx;
    for (i=0; i<NUM_CIRC_LINES; i++) {
      p = loglines[k%NUM_CIRC_LINES]; k++;
      if (*p) {
	fprintf(dbg_fd, "%s", p);
	*p = 0;
      }
    }
    fprintf(dbg_fd,"****************** END CIRC_BUF\n");
    fflush(dbg_fd);
  }
#else
  logptr += i;

  if ((dbg_fd==stderr) || ((logptr-logbuf) > logbuf_size) || (flg == -1)) {
    int fsz = logptr-logbuf;
    /* writing a big buffer can produce timer bursts, which under DPMI
     * can cause stack overflows!
     */
    if (terminal_pipe) {
      write(terminal_fd, logptr, fsz);
    }
    if (write(fileno(dbg_fd), logbuf, fsz) < 0) {
      if (errno==ENOSPC) leavedos(0x4c4c);
    }
    logptr = logbuf;
#if 1
    if (logfile_limit) {
      log_written += fsz;
      if (log_written > logfile_limit) {
        fflush(dbg_fd);
#if 1
        ftruncate(fileno(dbg_fd),0);
        fseek(dbg_fd, 0, SEEK_SET);
        log_written = 0;
#else
	fclose(dbg_fd);
	shut_debug = 1;
	dbg_fd = 0;	/* avoid recursion in leavedos() */
	leavedos(0);
#endif
      }
    }
#endif
  }
#endif
  return i;
}

static int in_log_printf=0;

int log_printf(int flg, const char *fmt, ...)
{
#ifdef CIRCULAR_LOGBUFFER
	static int first = 1;
#endif
	va_list args;
	int ret;

#ifdef CIRCULAR_LOGBUFFER
	if (first) {
	  int i;
	  logbuf = calloc((NUM_CIRC_LINES+4), SIZ_CIRC_LINES);
	  for (i=0; i<NUM_CIRC_LINES; i++)
	    loglines[i] = logbuf + SIZ_CIRC_LINES*i;
	  loglineidx = 0;
	  first=0;
	}
#endif
	if (in_log_printf) return 0;
	if (!(dosdebug_flags & DBGF_INTERCEPT_LOG)) {
		if (!flg || !dbg_fd ) return 0;
	}
	in_log_printf = 1;
	va_start(args, fmt);
	ret = vlog_printf(flg, fmt, args);
	va_end(args);
	in_log_printf = 0;
	return ret;
}

void verror(const char *fmt, va_list args) 
{
	char fmtbuf[1025];
	va_list orig_args;
	__va_copy(orig_args, args);

	if (fmt[0] == '@') {
		vlog_printf(10, fmt+1, args);
		vfprintf(stderr, fmt+1, orig_args);
	}
	else {
		fmtbuf[sizeof(fmtbuf)-1] = 0;
		snprintf(fmtbuf, sizeof(fmtbuf)-1, "ERROR: %s", fmt);
		vlog_printf(10, fmtbuf, args);
		vfprintf(stderr, fmtbuf, orig_args);
	}
	
}

void error(const char *fmt, ...)
{
	va_list args;
	va_start(args, fmt);
	verror(fmt, args);
	va_end(args);
}


/* write string to dos? */
int
p_dos_str(const char *fmt,...) {
  va_list args;
  static char buf[1025];
  char *s;
  int i;

  va_start(args, fmt);
  buf[sizeof(buf)-1] = 0;
  i = vsnprintf(buf, sizeof(buf)-1,  fmt, args);
  va_end(args);

  s = buf;
  g_printf("CONSOLE MSG: '%s'\n",buf);
  while (*s) 
	char_out(*s++, READ_BYTE(BIOS_CURRENT_SCREEN_PAGE));
  return i;
}
        
/* some stuff to handle reading of /proc */

static char *procfile_name=0;
static char *procbuf=0;
static char *procbufptr=0;
#define PROCBUFSIZE	4096
static char *proclastpos=0;
static char proclastdelim=0;

void close_proc_scan(void)
{
  if (procfile_name) free(procfile_name);
  if (procbuf) free(procbuf);
  procfile_name = procbuf = procbufptr = proclastpos = 0;
}

void open_proc_scan(char *name)
{
  int size, fd;
  close_proc_scan();
  fd = open(name, O_RDONLY);
  if (fd == -1) {
    error("cannot open %s\n", name);
    leavedos(5);
  }
  procfile_name = strdup(name);
  procbuf = malloc(PROCBUFSIZE);
  size = read(fd, procbuf, PROCBUFSIZE-1);
  procbuf[size] = 0;
  procbufptr = procbuf;
  close(fd);
}

void advance_proc_bufferptr(void)
{
  if (proclastpos) {
    procbufptr = proclastpos;
    if (proclastdelim == '\n') procbufptr++;
  }
}

void reset_proc_bufferptr(void)
{
  procbufptr = procbuf; proclastpos = 0;
}

char *get_proc_string_by_key(char *key)
{

  char *p;

  if (proclastpos) {
    *proclastpos = proclastdelim;
    proclastpos =0;
  }
  p = strstr(procbufptr, key);
  if (p) {
    if ((p == procbufptr) || (p[-1] == '\n')) {
      p += strlen(key);
      while (*p && isblank(*p)) p++;
      if (*p == ':') p++;
      while (*p && isblank(*p)) p++;
      proclastpos = p;
      while (*proclastpos && (*proclastpos != '\n')) proclastpos++;
      proclastdelim = *proclastpos;
      *proclastpos = 0;
      return p;
    }
  }
#if 0
  error("Unknown format on %s\n", procfile_name);
  leavedos(5);
#endif
  return 0; /* just to make GCC happy */
}

int get_proc_intvalue_by_key(char *key)
{
  char *p = get_proc_string_by_key(key);
  int val;

  if (p) {
    if (sscanf(p, "%d",&val) == 1) return val;
  }
  error("Unknown format on %s\n", procfile_name);
  leavedos(5);
  return -1; /* just to make GCC happy */
}


int integer_sqrt(int x)
{
	unsigned y;
	int delta;

	if (x < 1) return 0;
	if (x <= 1) return 1;
        y = power_of_2_sqrt(x);
	if ((y*y) == x) return y;
	delta = y >> 1;
	while (delta) {
		y += delta;
		if (y*y > x) y -= delta;
		delta >>= 1;
	}
	return y;
}

int exists_dir(char *name)
{
	struct stat st;
	if (stat(name, &st)) return 0;
	return (S_ISDIR(st.st_mode));
}

int exists_file(char *name)
{
	struct stat st;
	if (stat(name, &st)) return 0;
	return (S_ISREG(st.st_mode));
}

char *strcatdup(char *s1, char *s2)
{
	char *s;
	if (!s1 || !s2) return 0;
	s = malloc(strlen(s1)+strlen(s2)+1);
	if (!s) return 0;
	strcpy(s,s1);
	return strcat(s,s2);
}

char *assemble_path(char *dir, char *file, int append_pid)
{
	char *s;
	char pid[32] = "";
	if (append_pid) sprintf(pid, "%d", getpid());
	s = malloc(strlen(dir)+1+strlen(file)+strlen(pid)+1);
	if (!s) {
		fprintf(stderr, "out of memory, giving up\n");
		siglongjmp(NotJEnv, 0x4d);
	}
	sprintf(s, "%s/%s%s", dir, file, pid);
	return s;
}

char *mkdir_under(char *basedir, char *dir, int append_pid)
{
	char *s = basedir;

	if (dir) s = assemble_path(basedir, dir, append_pid);
	if (!exists_dir(s)) {
		if (mkdir(s, S_IRWXU)) {
			fprintf(stderr, "can't create local %s directory\n", s);
		}
	}
	return s;
}

char *get_path_in_HOME(char *path)
{
	char *home = getenv("HOME");

	if (!home) {
		fprintf(stderr, "odd environment, you don't have $HOME, giving up\n");
		leavedos(0x45);
	}
	if (!path) {
		return strdup(home);
	}
	return assemble_path(home, path, 0);
}

char *get_dosemu_local_home(void)
{
	return mkdir_under(get_path_in_HOME(".dosemu"), 0, 0);
}

int argparse(char *s, char *argvx[], int maxarg)
{
   int mode = 0;
   int argcx = 0;
   char delim = 0;

   maxarg --;
   for ( ; *s; s++) {
      if (!mode) {
         if (*s > ' ') {
            mode = 1;
            argvx[argcx++] = s;
            switch (*s) {
              case '"':
              case '\'':
                delim = *s;
                mode = 2;
            }
            if (argcx >= maxarg)
               break;
         }
      } else if (mode == 1) {
         if (*s <= ' ') {
            mode = 0;
            *s = 0x00;
         }
      } else {
         if (*s == delim) mode = 1;
      }
   }
   argvx[argcx] = 0;
   return(argcx);
}

void subst_file_ext(char *ptr)
{
#define ext_fix(s) { char *r=(s); \
		     while (*r) { *r=toupperDOS(*r); r++; } }
    static int subst_sys=2;

    if (ptr == NULL) {
      /* reset */
      subst_sys = 2;
      return;
    }

    /* skip leading drive name and \ */
    if (ptr[1]==':' && ptr[2]=='\\') ptr+=3;
    else if (ptr[0]=='\\') ptr++;

    if (config.emuini && !strncasecmp(ptr, "WINDOWS\\SYSTEM.INI", 18)) {
	ext_fix(config.emuini);
	sprintf(ptr, "WINDOWS\\SYSTEM.%s", config.emuini);
	d_printf("DISK: Substituted %s for system.ini\n", ptr+8);
	return;
    }

    if (subst_sys && config.emusys) {
        char config_name[6+1+3+1];
#if 0	/*
	 * NOTE: as the method used in fatfs.c can't handle multiple
	 * files to be faked, we can't do it here, because this would
	 * confuse more than doing anything valuable --Hans 2001/03/16
	 */

	/* skip the D for DCONFIG.SYS in DR-DOS */
	if (toupperDOS(ptr[0]) == 'D') ptr++;
#endif
        ext_fix(config.emusys);
        sprintf(config_name, "CONFIG.%-3s", config.emusys);
        if (subst_sys == 1 && !strequalDOS(ptr, config_name) &&
            !strequalDOS(ptr, "CONFIG.SYS")) {
            subst_sys = 0;
        } else if (strequalDOS(ptr, "CONFIG.SYS")) {
            strcpy(ptr, config_name);
	    d_printf("DISK: Substituted %s for CONFIG.SYS\n", ptr);
	    subst_sys = 1;
	}
    } 
}

void call_cmd(const char *cmd, int maxargs, const struct cmd_db *cmdtab,
	cmdprintf_func *printf)
{
   int argc1;
   char **argv1;
   char *tmpcmd;
   void (*cmdproc)(int, char *[]);
   const struct cmd_db *cmdp;

   tmpcmd = strdup(cmd);
   if (!tmpcmd) {
      if (printf) (*printf)("out of memory\n");
      return;
   }
   argv1 = malloc(maxargs * sizeof(char *));
   if (!argv1) {
      if (printf) (*printf)("out of memory\n");
      free(tmpcmd);
      return;
   };
   argc1 = argparse(tmpcmd, argv1, maxargs);
   if (argc1 < 1) {
      free(tmpcmd);
      free(argv1);
      return;
   }
   for (cmdp = cmdtab, cmdproc = NULL; cmdp->cmdproc; cmdp++) {
      if (!memcmp(cmdp->cmdname, argv1[0], strlen(argv1[0])+1)) {
         cmdproc = cmdp->cmdproc;
         break;
      }
   }
   if (!cmdproc) {
      if (printf) (*printf)("Command %s not found\n", argv1[0]);
   }
   else (*cmdproc)(argc1, argv1);
   free(tmpcmd);
   free(argv1);
}

void sigalarm_onoff(int on)
{
  static struct itimerval itv_old;
#ifdef X86_EMULATOR
  static struct itimerval itv_oldp;
#endif
  static struct itimerval itv;
  static volatile int is_off = 0;
  if (on) {
    if (is_off--) {
    	setitimer(ITIMER_REAL, &itv_old, NULL);
#ifdef X86_EMULATOR
    	setitimer(ITIMER_PROF, &itv_oldp, NULL);
#endif
    }
  }
  else if (!is_off++) {
    itv.it_interval.tv_sec = itv.it_interval.tv_usec = 0;
    itv.it_value = itv.it_interval;
    setitimer(ITIMER_REAL, &itv, &itv_old);
#ifdef X86_EMULATOR
    setitimer(ITIMER_PROF, &itv, &itv_oldp);
#endif
  }
}

void sigalarm_block(int block)
{
  static volatile int is_blocked = 0;
  sigset_t blockset;
  if (block) {
    if (!is_blocked++) {
      sigemptyset(&blockset);
      sigaddset(&blockset, SIGALRM);
      sigprocmask(SIG_BLOCK, &blockset, NULL);
    }
  }
  else if (is_blocked--) {
    sigemptyset(&blockset);
    sigaddset(&blockset, SIGALRM);
    sigprocmask(SIG_UNBLOCK, &blockset, NULL);
  }
}

/* dynamic readlink, adapted from "info libc" */
char *readlink_malloc (const char *filename)
{
  int size = 50;
  int nchars;
  char *buffer;

  do {
    size *= 2;
    nchars = 0;
    buffer = malloc(size);
    if (buffer != NULL) {
      nchars = readlink(filename, buffer, size);
      if (nchars < 0) {
        free(buffer);
        buffer = NULL;
      }
    }
  } while (nchars >= size);
  if (buffer != NULL)
    buffer[nchars] = '\0';
  return buffer;
}

void dosemu_error(char *fmt, ...)
{
    va_list args;
    va_start(args, fmt);
    verror(fmt, args);
    va_end(args);
    gdb_debug();
}

#ifdef USE_DL_PLUGINS
void *load_plugin(const char *plugin_name)
{
    char *fullname = malloc(strlen(dosemu_proc_self_exe) +
			    strlen(plugin_name) + 20);
    void *handle;
    char *slash;

    strcpy(fullname, dosemu_proc_self_exe);
    slash = strrchr(fullname, '/');
    if (slash == NULL) return NULL;
    sprintf(slash + 1, "libplugin_%s.so", plugin_name);
    handle = dlopen(fullname, RTLD_LAZY);
    free(fullname);
    if (handle != NULL)
	return handle;
    asprintf(&fullname, "%s/dosemu/libplugin_%s.so",
	     LIB_DEFAULT, plugin_name);
    handle = dlopen(fullname, RTLD_LAZY);
    free(fullname);
    if (handle != NULL)
	return handle;
    error("%s support not compiled in or not found:\n", plugin_name);
    error("%s\n", dlerror());
    return handle;
}
#else
void *load_plugin(const char *plugin_name)
{
    return NULL;
}
#endif

/* Ring buffer implementation */

void rng_init(struct rng_s *rng, size_t objnum, size_t objsize)
{
  rng->buffer = calloc(objnum, objsize);
  rng->objnum = objnum;
  rng->objsize = objsize;
  rng->tail = rng->objcnt = 0;
}

int rng_destroy(struct rng_s *rng)
{
  int ret = rng->objcnt;
  free(rng->buffer);
  rng->objcnt = 0;
  return ret;
}

int rng_get(struct rng_s *rng, void *buf)
{
  if (!rng->objcnt)
    return 0;
  if (buf)
    memcpy(buf, rng->buffer + rng->tail, rng->objsize);
  rng->tail += rng->objsize;
  rng->tail %= rng->objsize * rng->objnum;
  rng->objcnt--;
  return 1;
}

int rng_peek(struct rng_s *rng, int idx, void *buf)
{
  int obj_pos;
  if (rng->objcnt <= idx)
    return 0;
  obj_pos = (rng->tail + idx * rng->objsize) % (rng->objnum * rng->objsize);
  assert(buf);
  memcpy(buf, rng->buffer + obj_pos, rng->objsize);
  return 1;
}

int rng_put(struct rng_s *rng, void *obj)
{
  int head_pos, ret = 1;;
  head_pos = (rng->tail + rng->objcnt * rng->objsize) % (rng->objnum * rng->objsize);
  assert(head_pos <= (rng->objnum - 1) * rng->objsize);
  memcpy(rng->buffer + head_pos, obj, rng->objsize);
  rng->objcnt++;
  if (rng->objcnt > rng->objnum) {
    rng_get(rng, NULL);
    ret = 0;
  }
  assert(rng->objcnt <= rng->objnum);
  return ret;
}

int rng_put_const(struct rng_s *rng, int value)
{
  if (rng->objsize > sizeof(value)) {
    dosemu_error("rng_put_const for obj size=%i\n", rng->objsize);
    return 0;
  }
  return rng_put(rng, &value);
}

int rng_poke(struct rng_s *rng, int idx, void *buf)
{
  int obj_pos;
  if (rng->objcnt <= idx)
    return 0;
  obj_pos = (rng->tail + idx * rng->objsize) % (rng->objnum * rng->objsize);
  memcpy(rng->buffer + obj_pos, buf, rng->objsize);
  return 1;
}

int rng_add(struct rng_s *rng, int num, void *buf)
{
  int i, ret = 0;
  for (i = 0; i < num; i++)
    ret += rng_put(rng, (unsigned char *)buf + i * rng->objsize);
  return ret;
}

int rng_remove(struct rng_s *rng, int num, void *buf)
{
  int i, ret = 0;
  for (i = 0; i < num; i++)
    ret += rng_get(rng, buf ? (unsigned char *)buf + i * rng->objsize : NULL);
  return ret;
}

int rng_count(struct rng_s *rng)
{
  return rng->objcnt;
}

void rng_clear(struct rng_s *rng)
{
  rng->objcnt = 0;
}
