gvdevice.c

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/*************************************************************************
 * Copyright (c) 2011 AT&T Intellectual Property 
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors: Details at https://graphviz.org
 *************************************************************************/
 
/*
 *  This library forms the socket for run-time loadable device plugins.  
 */
 
#include "config.h"
 
#include <ctype.h>
#include <limits.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>
#include <errno.h>
#include <unistd.h>
 
#ifdef _WIN32
#include <fcntl.h>
#include <io.h>
#endif
 
#ifdef HAVE_LIBZ
#include <zlib.h>
 
#ifndef OS_CODE
#  define OS_CODE  0x03  /* assume Unix */
#endif
static const unsigned char z_file_header[] =
   {0x1f, 0x8b, /*magic*/ Z_DEFLATED, 0 /*flags*/, 0,0,0,0 /*time*/, 0 /*xflags*/, OS_CODE};
 
static z_stream z_strm;
static unsigned char *df;
static unsigned int dfallocated;
static uint64_t crc;
#endif /* HAVE_LIBZ */
 
#include <assert.h>
#include <cgraph/agxbuf.h>
#include <cgraph/startswith.h>
#include <cgraph/exit.h>
#include <common/const.h>
#include <gvc/gvplugin_device.h>
#include <gvc/gvcjob.h>
#include <gvc/gvcint.h>
#include <gvc/gvcproc.h>
#include <common/utils.h>
#include <gvc/gvio.h>
 
static size_t gvwrite_no_z(GVJ_t * job, const void *s, size_t len) {
    if (job->gvc->write_fn)   /* externally provided write discipline */
        return job->gvc->write_fn(job, s, len);
    if (job->output_data) {
        if (len > job->output_data_allocated - (job->output_data_position + 1)) {
            /* ensure enough allocation for string = null terminator */
            job->output_data_allocated = job->output_data_position + len + 1;
            job->output_data = realloc(job->output_data, job->output_data_allocated);
            if (!job->output_data) {
                job->common->errorfn("memory allocation failure\n");
                graphviz_exit(1);
            }
        }
        memcpy(job->output_data + job->output_data_position, s, len);
        job->output_data_position += len;
        job->output_data[job->output_data_position] = '\0'; /* keep null terminated */
        return len;
    }
    assert(job->output_file != NULL);
    return fwrite(s, sizeof(char), len, job->output_file);
}
 
static void auto_output_filename(GVJ_t *job)
{
    static agxbuf buf;
    char *fn;
 
    if (!(fn = job->input_filename))
        fn = "noname.gv";
    agxbput(&buf, fn);
    if (job->graph_index)
        agxbprint(&buf, ".%d", job->graph_index + 1);
    agxbputc(&buf, '.');
 
    {
        const char *src = job->output_langname;
        const char *src_end = src + strlen(src);
        for (const char *q = src_end; ; --q) {
            if (*q == ':') {
                agxbprint(&buf, "%.*s.", (int)(src_end - q - 1), q + 1);
                src_end = q;
            }
            if (q == src) {
                agxbprint(&buf, "%.*s", (int)(src_end - src), src);
                break;
            }
        }
    }
 
    job->output_filename = agxbuse(&buf);
}
 
/* gvdevice_initialize:
 * Return 0 on success, non-zero on failure
 */
int gvdevice_initialize(GVJ_t * job)
{
    gvdevice_engine_t *gvde = job->device.engine;
    GVC_t *gvc = job->gvc;
 
    if (gvde && gvde->initialize) {
        gvde->initialize(job);
    }
    else if (job->output_data) {
    }
    /* if the device has no initialization then it uses file output */
    else if (!job->output_file) {        /* if not yet opened */
        if (gvc->common.auto_outfile_names)
            auto_output_filename(job);
        if (job->output_filename) {
            job->output_file = fopen(job->output_filename, "w");
            if (job->output_file == NULL) {
                job->common->errorfn("Could not open \"%s\" for writing : %s\n",
                    job->output_filename, strerror(errno));
                /* perror(job->output_filename); */
                return 1;
            }
        }
        else
            job->output_file = stdout;
 
#ifdef HAVE_SETMODE
#ifdef O_BINARY
        if (job->flags & GVDEVICE_BINARY_FORMAT)
#ifdef _WIN32
                _setmode(fileno(job->output_file), O_BINARY);
#else
                setmode(fileno(job->output_file), O_BINARY);
#endif                  
#endif
#endif
    }
 
    if (job->flags & GVDEVICE_COMPRESSED_FORMAT) {
#ifdef HAVE_LIBZ
        z_stream *z = &z_strm;
 
        z->zalloc = 0;
        z->zfree = 0;
        z->opaque = 0;
        z->next_in = NULL;
        z->next_out = NULL;
        z->avail_in = 0;
 
        crc = crc32(0L, Z_NULL, 0);
 
        if (deflateInit2(z, Z_DEFAULT_COMPRESSION, Z_DEFLATED, -MAX_WBITS, MAX_MEM_LEVEL, Z_DEFAULT_STRATEGY) != Z_OK) {
            job->common->errorfn("Error initializing for deflation\n");
            return 1;
        }
        gvwrite_no_z(job, z_file_header, sizeof(z_file_header));
#else
        job->common->errorfn("No libz support.\n");
        return 1;
#endif
    }
    return 0;
}
 
size_t gvwrite (GVJ_t * job, const char *s, size_t len)
{
    size_t ret, olen;
 
    if (!len || !s)
        return 0;
 
    if (job->flags & GVDEVICE_COMPRESSED_FORMAT) {
#ifdef HAVE_LIBZ
        z_streamp z = &z_strm;
 
        size_t dflen = deflateBound(z, len);
        if (dfallocated < dflen) {
            dfallocated = dflen > UINT_MAX - 1 ? UINT_MAX : (unsigned)dflen + 1;
            df = realloc(df, dfallocated);
            if (! df) {
                job->common->errorfn("memory allocation failure\n");
                graphviz_exit(1);
            }
        }
 
#if ZLIB_VERNUM >= 0x1290
        crc = crc32_z(crc, (const unsigned char*)s, len);
#else
        crc = crc32(crc, (const unsigned char*)s, len);
#endif
 
        for (size_t offset = 0; offset < len; ) {
// Suppress Clang/GCC -Wcast-qual warnings. `next_in` is morally const.
#ifdef __GNUC__
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wcast-qual"
#endif
            z->next_in = (unsigned char *)s + offset;
#ifdef __GNUC__
#pragma GCC diagnostic pop
#endif
            const unsigned chunk = len - offset > UINT_MAX
                                 ? UINT_MAX : (unsigned)(len - offset);
            z->avail_in = chunk;
            z->next_out = df;
            z->avail_out = dfallocated;
            int r = deflate(z, Z_NO_FLUSH);
            if (r != Z_OK) {
                job->common->errorfn("deflation problem %d\n", r);
                graphviz_exit(1);
            }
 
            if ((olen = (size_t)(z->next_out - df))) {
                ret = gvwrite_no_z(job, df, olen);
                if (ret != olen) {
                    job->common->errorfn("gvwrite_no_z problem %d\n", ret);
                    graphviz_exit(1);
                }
            }
            offset += chunk - z->avail_in;
        }
 
#else
        (void)olen;
        job->common->errorfn("No libz support.\n");
        graphviz_exit(1);
#endif
    }
    else { /* uncompressed write */
        ret = gvwrite_no_z (job, s, len);
        if (ret != len) {
            job->common->errorfn("gvwrite_no_z problem %d\n", len);
            graphviz_exit(1);
        }
    }
    return len;
}
 
int gvferror (FILE* stream)
{
    GVJ_t *job = (GVJ_t*)stream;
 
    if (!job->gvc->write_fn && !job->output_data)
        return ferror(job->output_file);
 
    return 0;
}
 
int gvputs(GVJ_t * job, const char *s)
{
    size_t len = strlen(s);
 
    if (gvwrite (job, s, len) != len) {
        return EOF;
    }
    return 1;
}
 
int gvputs_xml(GVJ_t *job, const char *s) {
  const xml_flags_t flags = {.dash = 1, .nbsp = 1};
  return xml_escape(s, flags, (int (*)(void *, const char *))gvputs, job);
}
 
void gvputs_nonascii(GVJ_t *job, const char *s) {
  for (; *s != '\0'; ++s) {
    if (*s == '\\') {
      gvputs(job, "\\\\");
    } else if (isascii((int)*s)) {
      gvputc(job, *s);
    } else {
      gvprintf(job, "%03o", (unsigned)*s);
    }
  }
}
 
int gvputc(GVJ_t * job, int c)
{
    const char cc = (char)c;
 
    if (gvwrite (job, &cc, 1) != 1) {
        return EOF;
    }
    return c;
}
 
int gvflush (GVJ_t * job)
{
    if (job->output_file
      && ! job->external_context
      && ! job->gvc->write_fn) {
        return fflush(job->output_file);
    }
    else
        return 0;
}
 
static void gvdevice_close(GVJ_t * job)
{
    if (job->output_filename
      && job->output_file != stdout 
      && ! job->external_context) {
        if (job->output_file) {
            fclose(job->output_file);
            job->output_file = NULL;
        }
        job->output_filename = NULL;
    }
}
 
void gvdevice_format(GVJ_t * job)
{
    gvdevice_engine_t *gvde = job->device.engine;
 
    if (gvde && gvde->format)
        gvde->format(job);
    gvflush (job);
}
 
void gvdevice_finalize(GVJ_t * job)
{
    gvdevice_engine_t *gvde = job->device.engine;
    bool finalized_p = false;
 
    if (job->flags & GVDEVICE_COMPRESSED_FORMAT) {
#ifdef HAVE_LIBZ
        z_streamp z = &z_strm;
        unsigned char out[8] = "";
        int ret;
        int cnt = 0;
 
        z->next_in = out;
        z->avail_in = 0;
        z->next_out = df;
        z->avail_out = dfallocated;
        while ((ret = deflate (z, Z_FINISH)) == Z_OK && (cnt++ <= 100)) {
            gvwrite_no_z(job, df, (size_t)(z->next_out - df));
            z->next_out = df;
            z->avail_out = dfallocated;
        }
        if (ret != Z_STREAM_END) {
            job->common->errorfn("deflation finish problem %d cnt=%d\n", ret, cnt);
            graphviz_exit(1);
        }
        gvwrite_no_z(job, df, (size_t)(z->next_out - df));
 
        ret = deflateEnd(z);
        if (ret != Z_OK) {
            job->common->errorfn("deflation end problem %d\n", ret);
            graphviz_exit(1);
        }
        out[0] = (unsigned char)crc;
        out[1] = (unsigned char)(crc >> 8);
        out[2] = (unsigned char)(crc >> 16);
        out[3] = (unsigned char)(crc >> 24);
        out[4] = (unsigned char)z->total_in;
        out[5] = (unsigned char)(z->total_in >> 8);
        out[6] = (unsigned char)(z->total_in >> 16);
        out[7] = (unsigned char)(z->total_in >> 24);
        gvwrite_no_z(job, out, sizeof(out));
#else
        job->common->errorfn("No libz support\n");
        graphviz_exit(1);
#endif
    }
 
    if (gvde) {
        if (gvde->finalize) {
            gvde->finalize(job);
            finalized_p = true;
        }
    }
 
    if (! finalized_p) {
        /* if the device has no finalization then it uses file output */
        gvflush (job);
        gvdevice_close(job);
    }
}
 
void gvprintf(GVJ_t * job, const char *format, ...)
{
    agxbuf buf = {0};
    va_list argp;
 
    va_start(argp, format);
    int len = vagxbprint(&buf, format, argp);
    if (len < 0) {
        va_end(argp);
        agerrorf("gvprintf: %s\n", strerror(errno));
        return;
    }
    va_end(argp);
 
    gvwrite(job, agxbuse(&buf), (size_t)len);
    agxbfree(&buf);
}
 
 
/* Test with:
 *      cc -DGVPRINTNUM_TEST gvprintnum.c -o gvprintnum
 */
 
/* use macro so maxnegnum is stated just once for both double and string versions */
#define val_str(n, x) static double n = x; static char n##str[] = #x;
val_str(maxnegnum, -999999999999999.99)
 
static void gvprintnum(agxbuf *xb, double number) {
    /*
        number limited to a working range: maxnegnum >= n >= -maxnegnum
        suppressing trailing "0" and "."
     */
 
    if (number < maxnegnum) {           /* -ve limit */
        agxbput(xb, maxnegnumstr);
        return;
    }
    if (number > -maxnegnum) {          /* +ve limit */
        agxbput(xb, maxnegnumstr + 1); // +1 to skip the '-' sign
        return;
    }
 
    agxbprint(xb, "%.03f", number);
    agxbuf_trim_zeros(xb);
 
    // strip off unnecessary leading '0'
    {
        char *staging = agxbdisown(xb);
        if (startswith(staging, "0.")) {
            memmove(staging, &staging[1], strlen(staging));
        } else if (startswith(staging, "-0.")) {
            memmove(&staging[1], &staging[2], strlen(&staging[1]));
        }
        agxbput(xb, staging);
        free(staging);
    }
}
 
 
#ifdef GVPRINTNUM_TEST
int main (int argc, char *argv[])
{
    agxbuf xb = {0};
    char *buf;
    size_t len;
 
    double test[] = {
        -maxnegnum*1.1, -maxnegnum*.9,
        1e8, 10.008, 10, 1, .1, .01,
        .006, .005, .004, .001, 1e-8, 
        0, -0,
        -1e-8, -.001, -.004, -.005, -.006,
        -.01, -.1, -1, -10, -10.008, -1e8,
        maxnegnum*.9, maxnegnum*1.1
    };
    int i = sizeof(test) / sizeof(test[0]);
 
    while (i--) {
        gvprintnum(&xb, test[i]);
        buf = agxbuse(&xb);;
        fprintf (stdout, "%g = %s %d\n", test[i], buf, len);
    }
 
    agxbfree(&xb);
    graphviz_exit(0);
}
#endif
 
/* gv_trim_zeros
* Identify Trailing zeros and decimal point, if possible.
* Assumes the input is the result of %.02f printing.
*/
static size_t gv_trim_zeros(const char *buf) {
  char *dotp = strchr(buf, '.');
  if (dotp == NULL) {
    return strlen(buf);
  }
 
  // check this really is the result of %.02f printing
  assert(isdigit((int)dotp[1]) && isdigit((int)dotp[2]) && dotp[3] == '\0');
 
  if (dotp[2] == '0') {
    if (dotp[1] == '0') {
      return (size_t)(dotp - buf);
    } else {
      return (size_t)(dotp - buf) + 2;
    }
  }
 
  return strlen(buf);
}
 
void gvprintdouble(GVJ_t * job, double num)
{
    // Prevents values like -0
    if (num > -0.005 && num < 0.005)
    {
        gvwrite(job, "0", 1);
        return;
    }
 
    char buf[50];
 
    snprintf(buf, 50, "%.02f", num);
    size_t len = gv_trim_zeros(buf);
 
    gvwrite(job, buf, len);
}
 
void gvprintpointf(GVJ_t * job, pointf p)
{
    agxbuf xb = {0};
 
    gvprintnum(&xb, p.x);
    const char *buf = agxbuse(&xb);
    gvwrite(job, buf, strlen(buf));
    gvwrite(job, " ", 1);
    gvprintnum(&xb, p.y);
    buf = agxbuse(&xb);
    gvwrite(job, buf, strlen(buf));
    agxbfree(&xb);
} 
 
void gvprintpointflist(GVJ_t *job, pointf *p, size_t n) {
  const char *separator = "";
  for (size_t i = 0; i < n; ++i) {
    gvputs(job, separator);
    gvprintpointf(job, p[i]);
    separator = " ";
  }
}