Memory Leaking - C -

in same file have 2 routines. first store bytes 1 file. other give information routines process information.

boolean adin_memory(char* buffer, int size_chunck, int end_flag){     real_data=(sp16 *)malloc(size_chunck); //real_data -->global     memcpy(&(real_data[0]),&(buffer[0]),size_chunck);      pos_write += size_chunck;     global_size = size_chunck;     global_end_flag = end_flag;     //end_flag = 1 --> end of stream     //end_flag = 0 --> streaming     return true; } 

to prevent possibility of leaking using malloc. routine called several times. so, after repetitions of adin_memory , adin_read (where free), think memory starts fragment (i can see leak size of input file in task manager - increment of ram). right? how can prevent this? see leak put 1 breakpoint @ beginning , @ end of adin_memory @ task manager.

int adin_read(sp16 *buf, int sampnum) {   file *fp;   int cnt = 0;   fp = gfp;    //(.......)     if(global_end_flag == 1 || pos_write == pos_read){ return -1;}      for(i = pos_read/sizeof(sp16); <= sampnum; i++){          if(i >= pos_write/sizeof(sp16)) {                            cnt = i;              //(....)              break;          }          buf[i] = real_data[i];      }      pos_write = 0;       //(....)      free(real_data);      return cnt; } 

int adin_read(sp16 *buf, int sampnum) {   file *fp;   int cnt = 0;   fp = gfp;    //(.......)     if(global_end_flag == 1 || pos_write == pos_read){        /* leak possibly here. return without freeing.           ensure free called here also. , practice           make freed pointer point null can check ,           avoid double free problems. */               return -1;     }      for(i = pos_read/sizeof(sp16); <= sampnum; i++){          if(i >= pos_write/sizeof(sp16)) {                            cnt = i;              //(....)              break;          }          buf[i] = real_data[i];      }      pos_write = 0;       //(....)      free(real_data);      return cnt; }