base/drms/libs/api/drms_dsdsapi.c

/* dsdsapi.c */

#include <stdlib.h>
#include <dlfcn.h>
#include <stdio.h>
#include <string.h>
#include "drms_dsdsapi.h"

const char *DSDS_PortNS[] =
{
   "dsds",
   "ds_mdi",
   NULL
};

void *DSDS_GetFPtr(void *hDSDS, const char *symbol)
{
   void *ret = NULL;
   char *msg = NULL;

   if (hDSDS)
   {
      dlerror();
      ret = dlsym(hDSDS, symbol);
      if ((msg = dlerror()) != NULL)
      {
     /* symbol not found */
     fprintf(stderr, "Symbol %s not found: %s.\n", symbol, msg);
      }
   }

   return ret;
}

int DSDS_IsDSDSSpec(const char *spec)
{
   return (strstr(spec, "prog:") == spec);
}

int DSDS_IsDSDSPort(const char *query)
{
   int isport = 0;
   int ins = 0;
   const char *portns = NULL;

   while ((portns = DSDS_PortNS[ins]) != NULL)
   {
      if (strstr(query, portns) == query)
      {
         isport = 1;
         break;
      }

      ins++;
   }

   return isport;
}

int DSDS_GetDSDSParams(DRMS_SeriesInfo_t *si, char *out)
{
    int err = 1;
    char buf[kDSDS_MaxHandle];
    snprintf(buf, sizeof(buf), "%s", si->description);
    char *lasts;
    char *ans;
    
    if (si)
    {
        if ((ans = strtok_r(buf, "[]", &lasts)) != NULL)
        {
            snprintf(out, kDSDS_MaxHandle, "%s", ans);
            err = 0;
        }
    }
    
    return err;
}

int DSDS_SetDSDSParams(void *hDSDS, DRMS_SeriesInfo_t *si, DSDS_Handle_t in)
{
    int err = 1;
    
    if (hDSDS && si)
    {
        pDSDSFn_DSDS_handle_todesc_t pFn_DSDS_handle_todesc =
        (pDSDSFn_DSDS_handle_todesc_t)DSDS_GetFPtr(hDSDS, kDSDS_DSDS_HANDLE_TODESC);
        
        if (pFn_DSDS_handle_todesc)
        {
            kDSDS_Stat_t dsdsStat;
            (*pFn_DSDS_handle_todesc)(in, si->description, &dsdsStat);
            err = (dsdsStat != kDSDS_Stat_Success);
        }
    }
    
    return err;
}

void *DSDS_GetLibHandle(const char *libname, kDSDS_Stat_t *status)
{
   kDSDS_Stat_t stat = kDSDS_Stat_Success;
   void *ret = NULL;
   char lpath[PATH_MAX];
   char spath[PATH_MAX];
   char *msg = NULL;

#ifdef DRMS_ARCH
#else
   #error Ensure the DRMS_ARCH macro is defined in make_basic.mk
#endif

   /* Obtain library tree path relative to binary path. */
   if (readlink("/proc/self/exe", spath, sizeof(spath)) == -1)
   {
      fprintf(stderr, "Cannot locate this binary.\n");
      stat = kDSDS_Stat_CantOpenLibrary;
   }
   else
   {
      /* Find architecture subdirectory. */
      char *needle = NULL;

      if ((needle = strstr(spath, DRMS_ARCH)) != NULL)
      {
         needle += strlen(DRMS_ARCH);
         *needle = '\0';

         /* We have the path to the make output directory. Now we need 
          * to get the parent and append "lib/DRMS_ARCH/libname. "*/
         snprintf(lpath, 
                  sizeof(lpath), 
                  "%s/../lib/%s/%s",
                  spath,
                  DRMS_ARCH,
                  libname);
      }
      else
      {
         fprintf(stderr, "Cannot find architecture %s subpath.\n", DRMS_ARCH);
         stat = kDSDS_Stat_CantOpenLibrary;
      }
   }

   if (!stat)
   {
      dlerror();
      ret = dlopen(lpath, RTLD_NOW);
      if ((msg = dlerror()) != NULL)
      {
         /* library not found */
         fprintf(stderr, "dlopen(%s) error: %s.\n", lpath, msg);
         if (ret)
         {
            dlclose(ret);
            ret = NULL;
         }
         stat = kDSDS_Stat_CantOpenLibrary;
      }
   }
   
   if (status)
   {
      *status = stat;
   }

   return ret;
}

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