progs/cc-progress.c: Use `fstat' to discover the file size.

[catacomb] / progs / cc-progress.c

/* -*-c-*-
 *
 * Progress indicators for command-line tools
 *
 * (c) 2011 Straylight/Edgeware
 */

/*----- Licensing notice --------------------------------------------------*
 *
 * This file is part of Catacomb.
 *
 * Catacomb is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Library General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * Catacomb is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with Catacomb; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA 02111-1307, USA.
 */

/*----- Header files ------------------------------------------------------*/

#define _FILE_OFFSET_BITS 64

#include "config.h"

#include <unistd.h>

#include "cc.h"

#ifndef PATHSEP
#  if defined(__riscos)
#    define PATHSEP '.'
#  elif defined(__unix) || defined(unix)
#    define PATHSEP '/'
#  else
#    define PATHSEP '\\'
#  endif
#endif

/*----- Static data -------------------------------------------------------*/

static const char baton[] = "-\\|/";

/*----- Human-friendly unit printing --------------------------------------*/

struct unit {
  const char *name;
  int m;
};

/* --- @prhuman_time@ --- *
 *
 * Arguments:	@FILE *fp@ = stream to print on
 *		@unsigned long n@ = time in seconds to print
 *
 * Returns:	---
 *
 * Use:		Prints a time in some reasonable format.  The time takes up
 *		PRHUMAN_TIMEWD character spaces.
 */

#define PRHUMAN_TIMEWD 7

static void prhuman_time(FILE *fp, unsigned long n)
{
  const static struct unit utime[] = {
    { "s",  60 }, { "m", 60 }, { "h", 24 }, { "d", 0 }
  };

  unsigned long m = 0;
  const struct unit *u = utime;

  while (u[1].m && n > u[0].m*u[1].m) { n /= u->m; u++; }
  m = n / u[1].m; n %= u[0].m;
  if (m) fprintf(fp, "%3lu%s%02lu%s", m, u[1].name, n, u[0].name);
  else fprintf(fp, "    %2lu%s", n, u[0].name);
}

/* --- @prhuman_data@ --- *
 *
 * Arguments:	@FILE *fp@ = file to print on
 *		@off_t n@ = size to be printed
 *
 * Returns:	---
 *
 * Use:		Prints a data size in some reasonable format.  The data size
 *		takes up PRHUMAN_DATAWD character spaces.
 */

#define PRHUMAN_DATAWD 7

static void prhuman_data(FILE *fp, off_t n)
{
  const static struct unit udata[] = {
    { " ", 1024 }, { "k", 1024 }, { "M", 1024 }, { "G", 1024 },
    { "T", 1024 }, { "P", 1024 }, { "E", 1024 }, { "Z", 1024 },
    { "Y",    0 }
  };

  double x = n;
  const struct unit *u = udata;

  while (u->m && x >= u->m) { x /= u->m; u++; }
  fprintf(fp, "%6.1f%s", x, u->name);
}

/*----- Main code ---------------------------------------------------------*/

#define BARWD 16

/* --- @fprogress_init@ --- *
 *
 * Arguments:	@fprogress *f@ = progress context to be initialized
 *		@const char *name@ = file name string to show
 *		@FILE *fp@ = file we're reading from
 *
 * Returns:	Zero on success, nonzero if the file's state is now broken.
 *
 * Use:		Initializes a progress context.  Nothing is actually
 *		displayed yet.
 */

int fprogress_init(fprogress *f, const char *name, FILE *fp)
{
  const char *p;
  struct stat st;
  off_t o, sz = -1;
  size_t n;

  /* --- Set up the offset --- */

  o = lseek(fileno(fp), 0, SEEK_CUR);
  if (fstat(fileno(fp), &st)) return (-1);
  sz = (S_ISREG(st.st_mode)) ? st.st_size : -1;
  if (o != -1 && sz != -1) sz -= o;
  f->o = f->olast = 0; f->sz = sz;

  /* --- Set up the file name --- */

  n = strlen(name);
  if (n < sizeof(f->name))
    strcpy(f->name, name);
  else if ((p = strchr(name + n - sizeof(f->name) + 4, PATHSEP)) != 0)
    sprintf(f->name, "...%s", p);
  else {
    p = strrchr(name, PATHSEP);
    if (!p) sprintf(f->name, "%.*s...", (int)sizeof(f->name) - 4, name);
    else sprintf(f->name, "...%.*s...", (int)sizeof(f->name) - 7, p);
  }

  /* --- Set up some other stuff --- */

  f->start = f->last = time(0);
  f->bp = baton;

  /* --- Done --- */

  return (0);
}

/* --- @fprogress_clear@ --- *
 *
 * Arguments:	@fprogress *f@ = progress context
 *
 * Returns:	---
 *
 * Use:		Clears the progress display from the screen.
 */

void fprogress_clear(fprogress *f)
{
  fprintf(stderr, "\r%*s\r",
	  (int)(sizeof(f->name) + 2*PRHUMAN_DATAWD +
		PRHUMAN_TIMEWD + BARWD + 16),
	  "");
}

/* --- @fprogress_update@ --- *
 *
 * Arguments:	@fprogress *f@ = progress context
 *		@size_t n@ = how much progress has been made
 *
 * Returns:	---
 *
 * Use:		Maybe updates the display to show that some progress has been
 *		made.
 */

void fprogress_update(fprogress *f, size_t sz)
{
  time_t now = time(0);
  int i, n;

  /* --- See if there's anything to do --- */

  f->o += sz;
  if (difftime(now, f->last) < 1) return;
  f->last = now;

  /* --- See if we're going to lose the ETA and percentage indicators --- */

  if (f->olast < f->sz && f->o > f->sz) fprogress_clear(f);
  f->olast = f->o;

  /* --- Do the initial display --- */

  fprintf(stderr, "\r%-*s%c ",
	  (int)sizeof(f->name), f->name,
	  *f->bp++);
  if (!*f->bp) f->bp = baton;
  prhuman_data(stderr, f->o);

  /* --- More complicated display if we have a set size --- */

  if (f->sz > f->o) {
    fputc('/', stderr);
    prhuman_data(stderr, f->sz);
    fputs(" [", stderr);
    n = (f->o*BARWD + f->sz/2)/f->sz;
    for (i = 0; i < n; i++) fputc('.', stderr);
    fprintf(stderr, "%*s] %3d%% ETA ", BARWD - n, "",
	    (int)((f->o*100 + 50)/f->sz));
    prhuman_time(stderr, difftime(now, f->start)*(f->sz - f->o)/f->o);
  }
}

/* --- @fprogress_done@ --- *
 *
 * Arguments:	@fprogress *f@ = progress context
 *
 * Returns:	---
 *
 * Use:		Clear up the progress context and removes any display.
 */

void fprogress_done(fprogress *f) { fprogress_clear(f); }

/*----- That's all, folks -------------------------------------------------*/