a xbps virtual packages list parser for dxpb

bvirtpkg_read.c

#define _POSIX_C_SOURCE 200809L
#include <czmq.h>
#include <stdio.h>

// you'll need to `free` the living shit out of everything in this hash when destroying it!
zhash_t *bvirtpkg_read(const char * path) {
  zhash_t *retVal = zhash_new();

  // if argument is already a complete path to the file, set to `0` or remove `if` block.
  #if 1
    const char* innerpath = "/etc/defaults.virtual";
    char *filepath = malloc(strlen(path)+strlen(innerpath)+1);
    if(!filepath) return NULL;
    strcpy(filepath,path);
    strcat(filepath,innerpath);
    FILE *handle = fopen(filepath,"r");
    free(filepath);
  #else
    FILE *handle = fopen(path,"r");
  #endif

  if(!handle) return NULL;

  char line[1025],vpkg[1025],resto[1025];
  while (fgets(line, sizeof line, handle)) {
    if (*line == '#') continue; /* ignore comment line */
    if (sscanf(line, "%1024s %1024s", vpkg, resto) == 2) {
      char *virtualpkg = malloc(strlen(vpkg)+1);
      char *resolvesto = malloc(strlen(resto)+1);
      strcpy(virtualpkg,vpkg);
      strcpy(resolvesto,resto);
      zhash_insert(retVal, virtualpkg, resolvesto);
    }
  }

  return retVal;
}

#ifdef TEST_BUILD

  int main(int argc, char *argv[]) {
    if(argc<2) {
      printf("usage: %s /path/to/void-packages name-of-virtual-package\n",argv[0]);
      return 1;
    }
    zhash_t *hash = bvirtpkg_read(argv[1]);
    if(!hash) {
      printf("bvirtpkg_read(\"%s\") failed.\n",argv[1]);
      return 2;
    }
    char *found = zhash_lookup(hash,argv[2]);
    if(!found) {
      printf("zhash_lookup(\"%s\") failed.\n",argv[2]);
      return 3;
    }
    printf("\"%s\" => \"%s\"\n",argv[2],found);
    return 0;
  }

#endif

/* tested with:

$ gcc -DTEST_BUILD bvirtpkg_read.c -lczmq
$ ./a.out ~/void-packages ntp-daemon
"ntp-daemon" => "chrony"

*/