OSXCrashReporterInfo.m

//
//  OSXCrashReporterInfo.h
//  OSXCrashReporterInfo
//
//  Created by Seth Willits on 10/26/14.
//  Copyright (c) 2014 Araelium Group. All rights reserved.
//

#import <CoreFoundation/CoreFoundation.h>


void OSXCrashReporterInfoInitialize(void);
void __attribute__((overloadable)) OSXCrashReporterInfoSet(const char * string, size_t length);
void __attribute__((overloadable)) OSXCrashReporterInfoSet(const char * string);
void OSXCrashReporterInfoClear(void);






//
//  OSXCrashReporterInfo.m
//  OSXCrashReporterInfo
//
//  Created by Seth Willits on 10/26/14.
//  Copyright (c) 2014 Araelium Group. All rights reserved.
//

#import "OSXCrashReporterInfo.h"



// We declare a symbol with a standard/convention name
static char *__crashreporter_info__ = nil;

// Mark the __crashreporter_info__ field as "referenced dynamically"
// This means it won't get stripped and will be included in the resulting
// binary so the crash reporter can see it.
asm(".desc ___crashreporter_info__, 0x10");


typedef struct {
    dispatch_queue_t queue;
    size_t messageCapacity;
} OSXCrashReporterInfo;
static OSXCrashReporterInfo sInfo;




__attribute__((constructor))
void OSXCrashReporterInfoInitialize(void)
{
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        sInfo.queue = dispatch_queue_create("AGCrashReporterInfo", DISPATCH_QUEUE_SERIAL);
        sInfo.messageCapacity = 0;
        __crashreporter_info__ = nil;
    });
}



void __attribute__((overloadable)) OSXCrashReporterInfoSet(const char * string, size_t length)
{
    dispatch_sync(sInfo.queue, ^{
        if (length > 0) {
            if (!__crashreporter_info__) {
                sInfo.messageCapacity = length + 1;
                __crashreporter_info__ = malloc(sInfo.messageCapacity);
            }
            
            if (length > sInfo.messageCapacity) {
                __crashreporter_info__ = realloc(__crashreporter_info__, length + 1);
                if (__crashreporter_info__) {
                    sInfo.messageCapacity = length + 1;
                } else {
                    sInfo.messageCapacity = 0;
                }
            }
            
            if (__crashreporter_info__) {
                memcpy(__crashreporter_info__, string, length);
                __crashreporter_info__[length] = 0;
            }
        } else {
            if (__crashreporter_info__) {
                __crashreporter_info__[0] = 0;
            }
        }
    });
}



void __attribute__((overloadable)) OSXCrashReporterInfoSet(const char * string)
{
    if (string) {
        OSXCrashReporterInfoSet(string, strlen(string));
    } else {
        OSXCrashReporterInfoSet(NULL, 0);
    }
}



void OSXCrashReporterInfoClear()
{
    OSXCrashReporterInfoSet(NULL, 0);
}