J'ai une bibliothèque dynamique, comment savoir si elle appelle malloc pendant l'exécution?

Question

J'ai besoin de faire du réseautage dans uCsimm, Motorola Dragon Ball. Comme je lance uClinux avec un patch RTAI, et que j'ai besoin de performances en temps réel, tout malloc et ses amis ne sont pas souhaitables. J'ai le morceau de code suivant pour la bibliothèque dynamique socket. Comment savoir qu'il appelle malloc pendant l'exécution? Quand j'ai compilé en cygwin sur Windows, j'ai utilisé cygwin et j'ai trouvé qu'il utilise malloc, calloc, realloc & gratuitement. Comment savoir sur Ubuntu/Linux quelles fonctions sont appelées pendant l'exécution? Merci d'avance!

#include <stdio.h> 
#include <stdlib.h> 
#include <string.h> 
#include <sys/time.h> 
#include <sys/types.h> 
#include <sys/socket.h> 
#include <netinet/in.h> 
#include <errno.h> 
#include <unistd.h> 
#include <arpa/inet.h> 
/* BUFFER_LEN is 4096 bytes */ 
#define BUFFER_LEN 4096 
/* receiver port number */ 
#define RECEIVERPORT 2009 
/* Variable and structure definitions. */ 
int receiver_socket_d, client_socket_d, ret_val; 
unsigned int length = sizeof (unsigned int); 
int totalcnt = 0, on = 1; 
char temp; 
char buffer[BUFFER_LEN]; 
struct sockaddr_in serveraddr; 
struct sockaddr_in their_addr; 
fd_set read_fd; 
struct timeval timeout; 
int receiver_setup() 
{ 
    timeout.tv_sec = 5; 
    timeout.tv_usec = 0; 
    /* The socket() function returns a socket descriptor */ 
    /* representing an endpoint. The statement also */ 
    /* identifies that the INET (Internet Protocol) */ 
    /* address family with the TCP transport (SOCK_STREAM) */ 
    /* will be used for this socket. */ 
    /************************************************/ 
    /* Get a socket descriptor */ 
    if ((receiver_socket_d = socket(AF_INET, SOCK_STREAM, 0)) < 0) { 
     //perror("receiver-socket() error"); 
     /* Just exit */ 
     exit(-1); 
    } else 
     //printf("receiver-socket() is OK\n"); 
    /* The setsockopt() function is used to allow */ 
    /* the local address to be reused when the server */ 
    /* is restarted before the required wait time */ 
    /* expires. */ 
    /***********************************************/ 
    /* Allow socket descriptor to be reusable */ 
    if ((ret_val = setsockopt(receiver_socket_d, SOL_SOCKET, SO_REUSEADDR, (char *) & on, sizeof (on))) < 0) { 
     //perror("receiver-setsockopt() error"); 
     close(receiver_socket_d); 
     exit(-1); 
    } else 
     //printf("receiver-setsockopt() is OK\n"); 
    /* bind to an address */ 
    memset(&serveraddr, 0x00, sizeof (struct sockaddr_in)); 
    serveraddr.sin_family = AF_INET; 
    serveraddr.sin_port = htons(RECEIVERPORT); 
    serveraddr.sin_addr.s_addr = htonl(INADDR_ANY); 
    //printf("Using %s, listening at %d\n", inet_ntoa(serveraddr.sin_addr), RECEIVERPORT); 
    /* After the socket descriptor is created, a bind() */ 
    /* function gets a unique name for the socket. */ 
    /* In this example, the user sets the */ 
    /* s_addr to zero, which allows the system to */ 
    /* connect to any client that used port 3005. */ 
    if ((ret_val = bind(receiver_socket_d, (struct sockaddr *) & serveraddr, sizeof (serveraddr))) < 0) { 
     //perror("receiver-bind() error"); 
     /* Close the socket descriptor */ 
     close(receiver_socket_d); 
     /* and just exit */ 
     exit(-1); 
    } else 
     //printf("receiver-bind() is OK\n"); 
    /* The listen() function allows the server to accept */ 
    /* incoming client connections. In this example, */ 
    /* the backlog is set to 10. This means that the */ 
    /* system can queue up to 10 connection requests before */ 
    /* the system starts rejecting incoming requests.*/ 
    /*************************************************/ 
    /* Up to 10 clients can be queued */ 
    if ((ret_val = listen(receiver_socket_d, 10)) < 0) { 
     //perror("receiver-listen() error"); 
     close(receiver_socket_d); 
     exit(-1); 
    } else 
     //printf("receiver-Ready for client connection...\n"); 
    return 0; 
} 
int receiver_wait() 
{ 
    /* The server will accept a connection request */ 
    /* with this accept() function, provided the */ 
    /* connection request does the following: */ 
    /* - Is part of the same address family */ 
    /* - Uses streams sockets (TCP) */ 
    /* - Attempts to connect to the specified port */ 
    /***********************************************/ 
    /* accept() the incoming connection request. */ 
    unsigned int sin_size = sizeof (struct sockaddr_in); 
    if ((client_socket_d = accept(receiver_socket_d, (struct sockaddr *) & their_addr, &sin_size)) < 0) { 
     //perror("receiver-accept() error"); 
     close(receiver_socket_d); 
     exit(-1); 
    } else 
     //printf("receiver-accept() is OK\n"); 
    /*client IP*/ 
    //printf("receiver-new socket, client_socket_d is OK...\n"); 
    //printf("Got connection from client: %s\n", inet_ntoa(their_addr.sin_addr)); 
    /* The select() function allows the process to */ 
    /* wait for an event to occur and to wake up */ 
    /* the process when the event occurs. In this */ 
    /* example, the system notifies the process */ 
    /* only when data is available to read. */ 
    /***********************************************/ 
    /* Wait for up to 15 seconds on */ 
    /* select() for data to be read. */ 
    FD_ZERO(&read_fd); 
    FD_SET(client_socket_d, &read_fd); 
    ret_val = select(client_socket_d + 1, &read_fd, NULL, NULL, &timeout); 
    return 0; 
}; 
int receiver_read() 
{ 
    buffer[0] = 0; 
    buffer[1] = 0; 
    totalcnt = 0; 
    if ((ret_val == 1) && (FD_ISSET(client_socket_d, &read_fd))) { 
     /* Read data from the client. */ 
     while ((totalcnt < BUFFER_LEN) && (ret_val > 0)) { 
      /* When select() indicates that there is data */ 
      /* available, use the read() function to read */ 
      /* 4096 bytes of the string that the */ 
      /* client sent. */ 
      /***********************************************/ 
      /* read() from client */ 
      ret_val = read(client_socket_d, &buffer[totalcnt], (BUFFER_LEN - totalcnt)); 
      //printf("Received data from client: %s\n\n", buffer); 
      if (ret_val < 0) { 
       //perror("receiver-read() error"); 
       close(receiver_socket_d); 
       close(client_socket_d); 
       exit(-1); 
      } else if (ret_val == 0) { 
       //printf("Client program has issued a close()\n"); 
       //close(receiver_socket_d); 
       //close(client_socket_d); 
       //exit(-1); 
      } else { 
       totalcnt += ret_val; 
       //printf("receiver-read() is OK\n"); 
      } 
     } 
    } else if (ret_val < 0) { 
     //perror("receiver-select() error"); 
     close(receiver_socket_d); 
     close(client_socket_d); 
     exit(-1); 
    } else {/* ret_val == 0 */ 
     //printf("receiver-select() timed out.\n"); 

     close(client_socket_d); 
     receiver_wait(); 
     //close(receiver_socket_d); 
     //exit(-1); 
    } 

    return 0; 
} 

Answer 1

ltrace

Answer 2

Vous pouvez exécuter votre programme avec strace pour surveiller les appels système.

strace [-dffhiqrtttTvVxx] [-a column] [-e expr] ... [-o file] [-p pid] ... [-s strsize] [-u username] [-E var=val] ... [command [arg ...]]

par exemple,

starce ls

vous pouvez également utiliser valgrind compter les allocations

wild eyalm # valgrind ls 
... 
==15144== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 23 from 1) 
==15144== malloc/free: in use at exit: 21,159 bytes in 36 blocks. 
==15144== malloc/free: 124 allocs, 88 frees, 31,944 bytes allocated. 
==15144== For counts of detected errors, rerun with: -v 
==15144== searching for pointers to 36 not-freed blocks. 
==15144== checked 105,612 bytes. 
==15144== 
==15144== LEAK SUMMARY: 
==15144== definitely lost: 0 bytes in 0 blocks. 
==15144==  possibly lost: 0 bytes in 0 blocks. 
==15144== still reachable: 21,159 bytes in 36 blocks. 
==15144==   suppressed: 0 bytes in 0 blocks.