gstreamer/ext/ladspa/search.c

/* search.c

   Free software by Richard W.E. Furse. Do with as you will. No
   warranty. */

/*****************************************************************************/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <dirent.h>
#include <dlfcn.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <unistd.h>
#include <glib.h>

/*****************************************************************************/

#include "ladspa.h"
#include "utils.h"

/*****************************************************************************/

/* Search just the one directory. */
static void
    LADSPADirectoryPluginSearch
    (const char *pcDirectory,
    LADSPAPluginSearchCallbackFunction fCallbackFunction)
{

  char *pcFilename;
  DIR *psDirectory;
  LADSPA_Descriptor_Function fDescriptorFunction;
  long lDirLength;
  long iNeedSlash;
  struct dirent *psDirectoryEntry;
  void *pvPluginHandle;

  lDirLength = strlen (pcDirectory);
  if (!lDirLength)
    return;
  if (pcDirectory[lDirLength - 1] == '/')
    iNeedSlash = 0;
  else
    iNeedSlash = 1;

  psDirectory = opendir (pcDirectory);
  if (!psDirectory)
    return;

  while (1) {

    psDirectoryEntry = readdir (psDirectory);
    if (!psDirectoryEntry) {
      closedir (psDirectory);
      return;
    }

    pcFilename = malloc (lDirLength + strlen (psDirectoryEntry->d_name)
        + 1 + iNeedSlash);
    strcpy (pcFilename, pcDirectory);
    if (iNeedSlash)
      strcat (pcFilename, "/");
    strcat (pcFilename, psDirectoryEntry->d_name);

    pvPluginHandle = dlopen (pcFilename, RTLD_LAZY);
    if (pvPluginHandle) {
      /* This is a file and the file is a shared library! */

      dlerror ();
      fDescriptorFunction
          = (LADSPA_Descriptor_Function) dlsym (pvPluginHandle,
          "ladspa_descriptor");
      if (dlerror () == NULL && fDescriptorFunction) {
        /* We've successfully found a ladspa_descriptor function. Pass
           it to the callback function. */
        fCallbackFunction (pcFilename, pvPluginHandle, fDescriptorFunction);
      } else {
        /* It was a library, but not a LADSPA one. Unload it. */
        dlclose (pvPluginHandle);
      }
    }
    free (pcFilename);
  }
}

/*****************************************************************************/

void
LADSPAPluginSearch (LADSPAPluginSearchCallbackFunction fCallbackFunction)
{

  char *pcBuffer;
  const char *pcEnd;
  const char *pcLADSPAPath;
  const char *pcStart;
  char *search_path;

  /* thomasvs: I'm sorry, but I'm going to add glib stuff here.
   * I'm appending logical values for LADSPA_PATH here
   */

  search_path = getenv ("LADSPA_PATH");
  if (search_path) {
    pcLADSPAPath = g_strdup_printf ("%s:/usr/lib/ladspa:/usr/local/lib/ladspa",
        search_path);
  } else {
    pcLADSPAPath = g_strdup ("/usr/lib/ladspa:/usr/local/lib/ladspa");
  }

  if (!pcLADSPAPath) {
/*    fprintf(stderr, */
/*          "Warning: You do not have a LADSPA_PATH " */
/*          "environment variable set.\n"); */
    return;
  }

  pcStart = pcLADSPAPath;
  while (*pcStart != '\0') {
    pcEnd = pcStart;
    while (*pcEnd != ':' && *pcEnd != '\0')
      pcEnd++;

    pcBuffer = malloc (1 + pcEnd - pcStart);
    if (pcEnd > pcStart)
      strncpy (pcBuffer, pcStart, pcEnd - pcStart);
    pcBuffer[pcEnd - pcStart] = '\0';

    LADSPADirectoryPluginSearch (pcBuffer, fCallbackFunction);
    free (pcBuffer);

    pcStart = pcEnd;
    if (*pcStart == ':')
      pcStart++;
  }
  g_free ((gpointer) pcLADSPAPath);
}

/*****************************************************************************/

/* EOF */