term.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2010, Digium, Inc.
 *
 * Mark Spencer <[email protected]>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! \file
 *
 * \brief Terminal Routines
 *
 * \author Mark Spencer <[email protected]>
 */

/*** MODULEINFO
   <support_level>core</support_level>
 ***/

#include "asterisk.h"

#include "asterisk/_private.h"
#include <sys/time.h>
#include <signal.h>
#include <sys/stat.h>
#include <fcntl.h>

#include "asterisk/term.h"
#include "asterisk/lock.h"
#include "asterisk/utils.h"
#include "asterisk/threadstorage.h"

static int vt100compat;

static char enddata[80] = "";
static char quitdata[80] = "";

static const char * const termpath[] = {
   "/usr/share/terminfo",
   "/usr/local/share/misc/terminfo",
   "/usr/lib/terminfo",
   NULL
   };

AST_THREADSTORAGE(commonbuf);

struct commonbuf {
   short which;
   char buffer[AST_TERM_MAX_ROTATING_BUFFERS][AST_TERM_MAX_ESCAPE_CHARS];
};

static int opposite(int color)
{
   int lookup[] = {
      /* BLACK */ COLOR_BLACK,
      /* RED */ COLOR_MAGENTA,
      /* GREEN */ COLOR_GREEN,
      /* BROWN */ COLOR_BROWN,
      /* BLUE */ COLOR_CYAN,
      /* MAGENTA */ COLOR_RED,
      /* CYAN */ COLOR_BLUE,
      /* WHITE */ COLOR_BLACK };
   return color ? lookup[color - 30] : 0;
}

/* Ripped off from Ross Ridge, but it's public domain code (libmytinfo) */
static short convshort(char *s)
{
   register int a, b;

   a = (int) s[0] & 0377;
   b = (int) s[1] & 0377;

   if (a == 0377 && b == 0377)
      return -1;
   if (a == 0376 && b == 0377)
      return -2;

   return a + b * 256;
}

int ast_term_init(void)
{
   char *term = getenv("TERM");
   char termfile[256] = "";
   char buffer[512] = "";
   int termfd = -1, parseokay = 0, i;

   if (ast_opt_no_color) {
      return 0;
   }

   if (!ast_opt_console) {
      /* If any remote console is not compatible, we'll strip the color codes at that point */
      vt100compat = 1;
      goto end;
   }

   if (!term) {
      return 0;
   }

   for (i = 0;; i++) {
      if (termpath[i] == NULL) {
         break;
      }
      snprintf(termfile, sizeof(termfile), "%s/%c/%s", termpath[i], *term, term);
      termfd = open(termfile, O_RDONLY);
      if (termfd > -1) {
         break;
      }
   }
   if (termfd > -1) {
      int actsize = read(termfd, buffer, sizeof(buffer) - 1);
      short sz_names = convshort(buffer + 2);
      short sz_bools = convshort(buffer + 4);
      short n_nums   = convshort(buffer + 6);

      /* if ((sz_names + sz_bools) & 1)
         sz_bools++; */

      if (sz_names + sz_bools + n_nums < actsize) {
         /* Offset 13 is defined in /usr/include/term.h, though we do not
          * include it here, as it conflicts with include/asterisk/term.h */
         short max_colors = convshort(buffer + 12 + sz_names + sz_bools + 13 * 2);
         if (max_colors > 0) {
            vt100compat = 1;
         }
         parseokay = 1;
      }
      close(termfd);
   }

   if (!parseokay) {
      /* These comparisons should not be substrings nor case-insensitive, as
       * terminal types are very particular about how they treat suffixes and
       * capitalization.  For example, terminal type 'linux-m' does NOT
       * support color, while 'linux' does.  Not even all vt100* terminals
       * support color, either (e.g. 'vt100+fnkeys'). */
      if (!strcmp(term, "linux")) {
         vt100compat = 1;
      } else if (!strcmp(term, "xterm")) {
         vt100compat = 1;
      } else if (!strcmp(term, "xterm-color")) {
         vt100compat = 1;
      } else if (!strcmp(term, "xterm-256color")) {
         vt100compat = 1;
      } else if (!strncmp(term, "Eterm", 5)) {
         /* Both entries which start with Eterm support color */
         vt100compat = 1;
      } else if (!strcmp(term, "vt100")) {
         vt100compat = 1;
      } else if (!strncmp(term, "crt", 3)) {
         /* Both crt terminals support color */
         vt100compat = 1;
      }
   }

end:
   if (vt100compat) {
      /* Make commands show up in nice colors */
      if (ast_opt_light_background) {
         snprintf(enddata, sizeof(enddata), "%c[%dm", ESC, COLOR_BLACK);
      } else if (ast_opt_force_black_background) {
         snprintf(enddata, sizeof(enddata), "%c[%d;%d;%dm", ESC, ATTR_RESET, COLOR_WHITE, COLOR_BLACK + 10);
      } else {
         snprintf(enddata, sizeof(enddata), "%c[%dm", ESC, ATTR_RESET);
      }
      snprintf(quitdata, sizeof(quitdata), "%c[%dm", ESC, ATTR_RESET);
   }
   return 0;
}

char *term_color(char *outbuf, const char *inbuf, int fgcolor, int bgcolor, int maxout)
{
   int attr = 0;

   if (!vt100compat) {
      ast_copy_string(outbuf, inbuf, maxout);
      return outbuf;
   }
   if (!fgcolor) {
      ast_copy_string(outbuf, inbuf, maxout);
      return outbuf;
   }

   if (fgcolor & 128) {
      attr = ast_opt_light_background ? 0 : ATTR_BRIGHT;
      fgcolor &= ~128;
   }

   if (bgcolor) {
      bgcolor &= ~128;
   }

   if (ast_opt_light_background) {
      fgcolor = opposite(fgcolor);
   }

   if (ast_opt_force_black_background) {
      if (!bgcolor) {
         bgcolor = COLOR_BLACK;
      }
      snprintf(outbuf, maxout, "%c[%d;%d;%dm%s%s", ESC, attr, fgcolor, bgcolor + 10, inbuf, term_end());
   } else {
      snprintf(outbuf, maxout, "%c[%d;%dm%s%s", ESC, attr, fgcolor, inbuf, term_end());
   }
   return outbuf;
}

static void check_fgcolor(int *fgcolor, int *attr)
{
   *attr = ast_opt_light_background ? 0 : ATTR_BRIGHT;
   if (*fgcolor & 128) {
      *fgcolor &= ~128;
   }

   if (ast_opt_light_background) {
      *fgcolor = opposite(*fgcolor);
   }
}

static void check_bgcolor(int *bgcolor)
{
   if (*bgcolor) {
      *bgcolor &= ~128;
   }
}

static int check_colors_allowed(void)
{
   return vt100compat;
}

int ast_term_color_code(struct ast_str **str, int fgcolor, int bgcolor)
{
   int attr = 0;

   if (!check_colors_allowed()) {
      return -1;
   }

   check_fgcolor(&fgcolor, &attr);
   check_bgcolor(&bgcolor);

   if (ast_opt_force_black_background) {
      ast_str_append(str, 0, "%c[%d;%d;%dm", ESC, attr, fgcolor, COLOR_BLACK + 10);
   } else if (bgcolor) {
      ast_str_append(str, 0, "%c[%d;%d;%dm", ESC, attr, fgcolor, bgcolor + 10);
   } else {
      ast_str_append(str, 0, "%c[%d;%dm", ESC, attr, fgcolor);
   }

   return 0;
}

char *term_color_code(char *outbuf, int fgcolor, int bgcolor, int maxout)
{
   int attr = 0;

   if (!check_colors_allowed()) {
      *outbuf = '\0';
      return outbuf;
   }

   check_fgcolor(&fgcolor, &attr);
   check_bgcolor(&bgcolor);

   if (ast_opt_force_black_background) {
      snprintf(outbuf, maxout, "%c[%d;%d;%dm", ESC, attr, fgcolor, COLOR_BLACK + 10);
   } else if (bgcolor) {
      snprintf(outbuf, maxout, "%c[%d;%d;%dm", ESC, attr, fgcolor, bgcolor + 10);
   } else {
      snprintf(outbuf, maxout, "%c[%d;%dm", ESC, attr, fgcolor);
   }

   return outbuf;
}

const char *ast_term_color(int fgcolor, int bgcolor)
{
   struct commonbuf *cb = ast_threadstorage_get(&commonbuf, sizeof(*cb));
   char *buf;

   if (!cb) {
      return "";
   }
   buf = cb->buffer[cb->which++];
   if (cb->which == AST_TERM_MAX_ROTATING_BUFFERS) {
      cb->which = 0;
   }

   return term_color_code(buf, fgcolor, bgcolor, AST_TERM_MAX_ESCAPE_CHARS);
}

const char *ast_term_reset(void)
{
   return term_end();
}

char *term_strip(char *outbuf, const char *inbuf, int maxout)
{
   char *outbuf_ptr = outbuf;
   const char *inbuf_ptr = inbuf;

   while (outbuf_ptr < outbuf + maxout) {
      switch (*inbuf_ptr) {
         case ESC:
            while (*inbuf_ptr && (*inbuf_ptr != 'm'))
               inbuf_ptr++;
            break;
         default:
            *outbuf_ptr = *inbuf_ptr;
            outbuf_ptr++;
      }
      if (! *inbuf_ptr)
         break;
      inbuf_ptr++;
   }
   return outbuf;
}

/* filter escape sequences */
void term_filter_escapes(char *line)
{
   int i;
   int len = strlen(line);

   for (i = 0; i < len; i++) {
      if (line[i] != ESC)
         continue;
      if ((i < (len - 2)) &&
          (line[i + 1] == 0x5B)) {
         switch (line[i + 2]) {
         case 0x30:
         case 0x31:
         case 0x33:
            continue;
         }
      }
      /* replace ESC with a space */
      line[i] = ' ';
   }
}

const char *term_end(void)
{
   return enddata;
}

const char *term_quit(void)
{
   return quitdata;
}