/* od.c - Provide octal/hex dumps of data
 *
 * Copyright 2012 Andre Renaud <andre@bluewatersys.com>
 * Copyright 2012 Rob Landley <rob@landley.net>
 *
 * See http://opengroup.org/onlinepubs/9699919799/utilities/od.html

USE_OD(NEWTOY(od, "j#vN#xsodcbA:t*", TOYFLAG_USR|TOYFLAG_BIN))

config OD
  bool "od"
  default y
  help
    usage: od [-bdosxv] [-j #] [-N #] [-A doxn] [-t arg]

    -A	Address base (decimal, octal, hexdecimal, none)
    -t	output type(s) a (ascii) c (char) d (decimal) foux
*/

#define FOR_od
#include "toys.h"

GLOBALS(
  struct arg_list *output_base;
  char *address_base;
  long max_count;
  long jump_bytes;

  unsigned types, leftover, star, address_idx;
  char *buf;
  uint64_t bufs[4]; // force 64-bit alignment
  off_t pos;
)

static char *ascii = "nulsohstxetxeotenqackbel bs ht nl vt ff cr so si"
  "dledc1dc2dc3dc4naksynetbcan emsubesc fs gs rs us sp";

struct odtype {
  int type;
  int size;
};

static void od_outline(void)
{
  unsigned flags = toys.optflags;
  char *abases[] = {"", "%07d", "%07o", "%06x"};
  struct odtype *types = (struct odtype *)toybuf, *t;
  int i, len;

  if (TT.leftover<16) memset(TT.buf+TT.leftover, 0, 16-TT.leftover);

  // Handle duplciate lines as *
  if (!(flags&FLAG_v) && TT.jump_bytes != TT.pos && TT.leftover
    && !memcmp(TT.bufs, TT.bufs + 2, 16))
  {
    if (!TT.star) {
      xputs("*");
      TT.star++;
    }

  // Print line position
  } else {
    TT.star = 0;

    xprintf(abases[TT.address_idx], TT.pos);
    if (!TT.leftover) {
      if (TT.address_idx) xputc('\n');
      return;
    }
  }

  TT.pos += len = TT.leftover;
  TT.leftover = 0;
  if (TT.star) return;

  // For each output type, print one line

  for (i=0; i<TT.types; i++) {
    int j = 0, pad = i ? 8 : 0;
    char buf[128];

    t = types+i;
    while (j<len) {
      unsigned k;
      int throw = 0;

      // Handle ascii
      if (t->type < 2) {
        char c = TT.buf[j++];
        pad += 4;

        if (!t->type) {
          c &= 127;
          if (c<=32) sprintf(buf, "%.3s", ascii+(3*c));
          else if (c==127) strcpy(buf, "del");
          else sprintf(buf, "%c", c);
        } else {
          char *bfnrtav = "\b\f\n\r\t\a\v", *s = strchr(bfnrtav, c);
          if (s) sprintf(buf, "\\%c", "bfnrtav0"[s-bfnrtav]);
          else if (c < 32 || c >= 127) sprintf(buf, "%03o", c);
          else {
            // TODO: this should be UTF8 aware.
            sprintf(buf, "%c", c);
          }
        }
      } else if (CFG_TOYBOX_FLOAT && t->type == 6) {
        long double ld;
        union {float f; double d; long double ld;} fdl;

        memcpy(&fdl, TT.buf+j, t->size);
        j += t->size;
        if (sizeof(float) == t->size) {
          ld = fdl.f;
          pad += (throw = 8)+7;
        } else if (sizeof(double) == t->size) {
          ld = fdl.d;
          pad += (throw = 17)+8;
        } else if (sizeof(long double) == t->size) {
          ld = fdl.ld;
          pad += (throw = 21)+9;
        } else error_exit("bad -tf '%d'", t->size);

        sprintf(buf, "%.*Le", throw, ld);
      // Integer types
      } else {
        unsigned long long ll = 0, or;
        char *c[] = {"%*lld", "%*llu", "%0*llo", "%0*llx"},
          *class = c[t->type-2];

        // Work out width of field
        if (t->size == 8) {
          or = -1LL;
          if (t->type == 2) or >>= 1;
        } else or = (1LL<<(8*t->size))-1;
        throw = sprintf(buf, class, 0, or);

        // Accumulate integer based on size argument
        for (k=0; k < t->size; k++) {
          or = TT.buf[j++];
          ll |= or << (8*(IS_BIG_ENDIAN ? t->size-k-1 : k));
        }

        // Handle negative values
        if (t->type == 2) {
          or = sizeof(or) - t->size;
          throw++;
          if (or && (ll & (1l<<((8*t->size)-1))))
            ll |= ((or<<(8*or))-1) << (8*t->size);
        }

        sprintf(buf, class, throw, ll);
        pad += throw+1;
      }
      xprintf("%*s", pad, buf);
      pad = 0;
    }
    xputc('\n');
  }

  // buffer toggle for "same as last time" check.
  TT.buf = (char *)((TT.buf == (char *)TT.bufs) ? TT.bufs+2 : TT.bufs);
}

static void do_od(int fd, char *name)
{
  // Skip input, possibly more than one entire file.
  if (TT.jump_bytes < TT.pos) {
    off_t off = lskip(fd, TT.jump_bytes);
    if (off > 0) TT.pos += off;
    if (TT.jump_bytes < TT.pos) return;
  }

  for(;;) {
    char *buf = TT.buf + TT.leftover;
    int len = 16 - TT.leftover;

    if (toys.optflags & FLAG_N) {
      if (!TT.max_count) break;
      if (TT.max_count < len) len = TT.max_count;
    }

    len = readall(fd, buf, len);
    if (len < 0) {
      perror_msg("%s", name);
      break;
    }
    if (TT.max_count) TT.max_count -= len;
    TT.leftover += len;
    if (TT.leftover < 16) break;

    od_outline();
  }
}

static void append_base(char *base)
{
  char *s = base;
  struct odtype *types = (struct odtype *)toybuf;
  int type;

  for (;;) {
    int size = 1;

    if (!*s) return;
    if (TT.types >= sizeof(toybuf)/sizeof(struct odtype)) break;
    if (-1 == (type = stridx("acduox"USE_TOYBOX_FLOAT("f"), *(s++)))) break;

    if (isdigit(*s)) {
      size = strtol(s, &s, 10);
      if (type < 2 && size != 1) break;
      if (CFG_TOYBOX_FLOAT && type == 6 && size == sizeof(long double));
      else if (size < 0 || size > 8) break;
    } else if (CFG_TOYBOX_FLOAT && type == 6) {
      int sizes[] = {sizeof(float), sizeof(double), sizeof(long double)};
      if (-1 == (size = stridx("FDL", *s))) size = sizeof(double);
      else {
        s++;
        size = sizes[size];
      }
    } else if (type > 1) {
      if (-1 == (size = stridx("CSIL", *s))) size = 4;
      else {
        s++;
        size = 1 << size;
      }
    }

    types[TT.types].type = type;
    types[TT.types].size = size;
    TT.types++;
  }

  error_exit("bad -t %s", base);
}

void od_main(void)
{
  struct arg_list *arg;

  TT.buf = (char *)TT.bufs;

  if (!TT.address_base) TT.address_idx = 2;
  else if (0>(TT.address_idx = stridx("ndox", *TT.address_base)))
    error_exit("bad -A '%c'", *TT.address_base);

  // Collect -t entries

  for (arg = TT.output_base; arg; arg = arg->next) append_base(arg->arg);
  if (toys.optflags & FLAG_b) append_base("o1");
  if (toys.optflags & FLAG_d) append_base("u2");
  if (toys.optflags & FLAG_o) append_base("o2");
  if (toys.optflags & FLAG_s) append_base("d2");
  if (toys.optflags & FLAG_x) append_base("x2");
  if (!TT.output_base) append_base("o2");

  loopfiles(toys.optargs, do_od);

  if (TT.leftover) od_outline();
  od_outline();
}