bcsignals.C

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#include "bcsignals.h"
#include "bcwindowbase.inc"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

BC_Signals* BC_Signals::global_signals = 0;
static int signal_done = 0;
static int table_id = 0;

static bc_locktrace_t* new_bc_locktrace(void *ptr, 
        char *title, 
        char *location)
{
        bc_locktrace_t *result = (bc_locktrace_t*)malloc(sizeof(bc_locktrace_t));
        result->ptr = ptr;
        result->title = title;
        result->location = location;
        result->is_owner = 0;
        result->id = table_id++;
        return result;
}





typedef struct
{
        int size;
        void *ptr;
        char *location;
} bc_buffertrace_t;

static bc_buffertrace_t* new_bc_buffertrace(int size, void *ptr, char *location)
{
        bc_buffertrace_t *result = (bc_buffertrace_t*)malloc(sizeof(bc_buffertrace_t));
        result->size = size;
        result->ptr = ptr;
        result->location = location;
        return result;
}






// Need our own table to avoid recursion with the memory manager
typedef struct
{
        void **values;
        int size;
        int allocation;
} bc_table_t;

static void* append_table(bc_table_t *table, void *ptr)
{
        if(table->allocation <= table->size)
        {
                if(table->allocation)
                {
                        int new_allocation = table->allocation * 2;
                        void **new_values = (void**)calloc(new_allocation, sizeof(void*));
                        memcpy(new_values, table->values, sizeof(void*) * table->size);
                        free(table->values);
                        table->values = new_values;
                        table->allocation = new_allocation;
                }
                else
                {
                        table->allocation = 4096;
                        table->values = (void**)calloc(table->allocation, sizeof(void*));
                }
        }

        table->values[table->size++] = ptr;
        return ptr;
}

static void clear_table(bc_table_t *table, int delete_objects)
{
        if(delete_objects)
        {
                for(int i = 0; i < table->size; i++)
                {
                        free(table->values[i]);
                }
        }
        table->size = 0;
}

static void clear_table_entry(bc_table_t *table, int number, int delete_object)
{
        if(delete_object) free(table->values[number]);
        for(int i = number; i < table->size - 1; i++)
        {
                table->values[i] = table->values[i + 1];
        }
        table->size--;
}


// Table of functions currently running.
static bc_table_t execution_table = { 0, 0, 0 };

// Table of locked positions
static bc_table_t lock_table = { 0, 0, 0 };

// Table of buffers
static bc_table_t memory_table = { 0, 0, 0 };

static bc_table_t temp_files = { 0, 0, 0 };

// Can't use Mutex because it would be recursive
static pthread_mutex_t *lock = 0;
static pthread_mutex_t *handler_lock = 0;
// Don't trace memory until this is true to avoid initialization
static int trace_memory = 0;


static char* signal_titles[] =
{
        "NULL",
        "SIGHUP",
        "SIGINT",
        "SIGQUIT",
        "SIGILL",
        "SIGTRAP",
        "SIGABRT",
        "SIGBUS",
        "SIGFPE",
        "SIGKILL",
        "SIGUSR1",
        "SIGSEGV",
        "SIGUSR2",
        "SIGPIPE",
        "SIGALRM",
        "SIGTERM"
};

static void signal_entry(int signum)
{
        signal(signum, SIG_DFL);

        pthread_mutex_lock(handler_lock);
        if(signal_done)
        {
                pthread_mutex_unlock(handler_lock);
                exit(0);
        }

        signal_done = 1;
        pthread_mutex_unlock(handler_lock);


        printf("signal_entry: got %s my pid=%d execution table size=%d:\n", 
                signal_titles[signum],
                getpid(),
                execution_table.size);

        BC_Signals::dump_traces();
        BC_Signals::dump_locks();
        BC_Signals::dump_buffers();
        BC_Signals::delete_temps();

// Call user defined signal handler
        BC_Signals::global_signals->signal_handler(signum);

        exit(0);
}

static void signal_entry_recoverable(int signum)
{
        printf("signal_entry_recoverable: got %s my pid=%d\n", 
                signal_titles[signum],
                getpid());
}

BC_Signals::BC_Signals()
{
}

void BC_Signals::dump_traces()
{
// Dump trace table
        if(execution_table.size)
        {
                for(int i = 0; i < execution_table.size; i++)
                        printf("    %s\n", execution_table.values[i]);
        }

}

void BC_Signals::dump_locks()
{
// Dump lock table
        printf("signal_entry: lock table size=%d\n", lock_table.size);
        for(int i = 0; i < lock_table.size; i++)
        {
                bc_locktrace_t *table = (bc_locktrace_t*)lock_table.values[i];
                printf("    %p %s %s %s\n", 
                        table->ptr,
                        table->title,
                        table->location,
                        table->is_owner ? "*" : "");
        }

}

void BC_Signals::dump_buffers()
{
        pthread_mutex_lock(lock);
// Dump buffer table
        printf("BC_Signals::dump_buffers: buffer table size=%d\n", memory_table.size);
        for(int i = 0; i < memory_table.size; i++)
        {
                bc_buffertrace_t *entry = (bc_buffertrace_t*)memory_table.values[i];
                printf("    %d %p %s\n", entry->size, entry->ptr, entry->location);
        }
        pthread_mutex_unlock(lock);
}

void BC_Signals::delete_temps()
{
        pthread_mutex_lock(lock);
        printf("BC_Signals::delete_temps: deleting %d temp files\n", temp_files.size);
        for(int i = 0; i < temp_files.size; i++)
        {
                printf("    %s\n", (char*)temp_files.values[i]);
                remove((char*)temp_files.values[i]);
        }
        pthread_mutex_unlock(lock);
}

void BC_Signals::set_temp(char *string)
{
        char *new_string = strdup(string);
        append_table(&temp_files, new_string);
}

void BC_Signals::unset_temp(char *string)
{
        for(int i = 0; i < temp_files.size; i++)
        {
                if(!strcmp((char*)temp_files.values[i], string))
                {
                        clear_table_entry(&temp_files, i, 1);
                        break;
                }
        }
}


void BC_Signals::initialize()
{
        BC_Signals::global_signals = this;
        lock = (pthread_mutex_t*)calloc(1, sizeof(pthread_mutex_t));
        handler_lock = (pthread_mutex_t*)calloc(1, sizeof(pthread_mutex_t));
        pthread_mutex_init(lock, 0);
        pthread_mutex_init(handler_lock, 0);

        initialize2();
}


void BC_Signals::initialize2()
{
        signal(SIGHUP, signal_entry);
        signal(SIGINT, signal_entry);
        signal(SIGQUIT, signal_entry);
        // SIGKILL cannot be stopped
        // signal(SIGKILL, signal_entry);
        signal(SIGSEGV, signal_entry);
        signal(SIGTERM, signal_entry);
        signal(SIGFPE, signal_entry_recoverable);
        signal(SIGPIPE, signal_entry_recoverable);
}


void BC_Signals::signal_handler(int signum)
{
printf("BC_Signals::signal_handler\n");
//      exit(0);
}

char* BC_Signals::sig_to_str(int number)
{
        return signal_titles[number];
}

#define TOTAL_TRACES 100

void BC_Signals::new_trace(char *text)
{
        if(!global_signals) return;
        pthread_mutex_lock(lock);
        if(execution_table.size >= TOTAL_TRACES)
                clear_table(&execution_table, 1);
        append_table(&execution_table, strdup(text));
        pthread_mutex_unlock(lock);
}

void BC_Signals::new_trace(const char *file, const char *function, int line)
{
        char string[BCTEXTLEN];
        snprintf(string, BCTEXTLEN, "%s: %s: %d", file, function, line);
        new_trace(string);
}

void BC_Signals::delete_traces()
{
        if(!global_signals) return;
        pthread_mutex_lock(lock);
        clear_table(&execution_table, 0);
        pthread_mutex_unlock(lock);
}

#define TOTAL_LOCKS 100

int BC_Signals::set_lock(void *ptr, 
        char *title, 
        char *location)
{
        if(!global_signals) return 0;
        bc_locktrace_t *table = 0;
        int id_return = 0;

        pthread_mutex_lock(lock);
        if(lock_table.size >= TOTAL_LOCKS)
                clear_table(&lock_table, 0);

// Put new lock entry
        table = new_bc_locktrace(ptr, title, location);
        append_table(&lock_table, table);
        id_return = table->id;

        pthread_mutex_unlock(lock);
        return id_return;
}

void BC_Signals::set_lock2(int table_id)
{
        if(!global_signals) return;

        bc_locktrace_t *table = 0;
        pthread_mutex_lock(lock);
        for(int i = lock_table.size - 1; i >= 0; i--)
        {
                table = (bc_locktrace_t*)lock_table.values[i];
// Got it.  Hasn't been unlocked/deleted yet.
                if(table->id == table_id)
                {
                        table->is_owner = 1;
                        pthread_mutex_unlock(lock);
                        return;
                }
        }
        pthread_mutex_unlock(lock);
}

void BC_Signals::unset_lock2(int table_id)
{
        if(!global_signals) return;

        bc_locktrace_t *table = 0;
        pthread_mutex_lock(lock);
        for(int i = lock_table.size - 1; i >= 0; i--)
        {
                table = (bc_locktrace_t*)lock_table.values[i];
                if(table->id == table_id)
                {
                        clear_table_entry(&lock_table, i, 1);
                        pthread_mutex_unlock(lock);
                        return;
                }
        }
        pthread_mutex_unlock(lock);
}

void BC_Signals::unset_lock(void *ptr)
{
        if(!global_signals) return;

        bc_locktrace_t *table = 0;
        pthread_mutex_lock(lock);

// Take off currently held entry
        for(int i = 0; i < lock_table.size; i++)
        {
                table = (bc_locktrace_t*)lock_table.values[i];
                if(table->ptr == ptr)
                {
                        if(table->is_owner)
                        {
                                clear_table_entry(&lock_table, i, 1);
                                pthread_mutex_unlock(lock);
                                return;
                        }
                }
        }

        pthread_mutex_unlock(lock);
}


void BC_Signals::unset_all_locks(void *ptr)
{
        if(!global_signals) return;
        pthread_mutex_lock(lock);
// Take off previous lock entry
        for(int i = 0; i < lock_table.size; i++)
        {
                bc_locktrace_t *table = (bc_locktrace_t*)lock_table.values[i];
                if(table->ptr == ptr)
                {
                        clear_table_entry(&lock_table, i, 1);
                }
        }
        pthread_mutex_unlock(lock);
}


void BC_Signals::enable_memory()
{
        trace_memory = 1;
}

void BC_Signals::disable_memory()
{
        trace_memory = 0;
}


void BC_Signals::set_buffer(int size, void *ptr, char* location)
{
        if(!global_signals) return;
        if(!trace_memory) return;

        pthread_mutex_lock(lock);
        append_table(&memory_table, new_bc_buffertrace(size, ptr, location));
        pthread_mutex_unlock(lock);
}

int BC_Signals::unset_buffer(void *ptr)
{
        if(!global_signals) return 0;
        if(!trace_memory) return 0;
        pthread_mutex_lock(lock);
        for(int i = 0; i < memory_table.size; i++)
        {
                if(((bc_buffertrace_t*)memory_table.values[i])->ptr == ptr)
                {
                        clear_table_entry(&memory_table, i, 1);
                        pthread_mutex_unlock(lock);
                        return 0;
                }
        }
        pthread_mutex_unlock(lock);
        fprintf(stderr, "BC_Signals::unset_buffer buffer %p not found.\n", ptr);
        return 1;
}













#ifdef TRACE_MEMORY

// Vice president of memory management
void* operator new(size_t size) 
{
//printf("new 1 %d\n", size);
    void *result = malloc(size);
        BUFFER(size, result, "new");
//printf("new 2 %d\n", size);
        return result;
}

void* operator new[](size_t size) 
{
//printf("new [] 1 %d\n", size);
    void *result = malloc(size);
        BUFFER(size, result, "new []");
//printf("new [] 2 %d\n", size);
        return result;
}

void operator delete(void *ptr) 
{
//printf("delete 1 %p\n", ptr);
        UNBUFFER(ptr);
//printf("delete 2 %p\n", ptr);
    free(ptr);
}

void operator delete[](void *ptr) 
{
//printf("delete [] 1 %p\n", ptr);
        UNBUFFER(ptr);
    free(ptr);
//printf("delete [] 2 %p\n", ptr);
}


#endif

---