i´m new to apple´s core graphic for PDF. I developing an app to display a PDF with links/actions which will go to the page x/y. The first code/help i found was here. But that code is for external URLs to websites. In the pdf ref doc from Adobe.com i found out, that i have to use the "GoTo" action. I´ve tried all 3 types (object, name and byte string) but it doesn´t work. Can anyone get me a hint, what i´m doing wrong?
for (unsigned i = 0; i < arrayCount; ++i) {
CGPDFObjectRef aDictObj;
if (!CGPDFArrayGetObject(outputArray, i, &aDictObj)) {
return;
} // END if
CGPDFDictionaryRef annotDict;
if(!CGPDFObjectGetValue(aDictObj, kCGPDFObjectTypeDictionary, &annotDict)) {
return;
} // END if
CGPDFDictionaryRef aDict;
if(!CGPDFDictionaryGetDictionary(annotDict, "A", &aDict)) {
return;
} // END if
const char *gotoNameRef;
CGPDFArrayRef gotoArray;
if (CGPDFDictionaryGetArray(aDict, "D", &gotoArray)) {
if (!CGPDFArrayGetName(gotoArray, 0, &gotoNameRef)) {
return;
}
} else {
return;
} // END if
int gotoCounter = CGPDFArrayGetCount(gotoArray);
CGPDFArrayRef rectArray;
if(!CGPDFDictionaryGetArray(annotDict, "Rect", &rectArray)) {
return;
} // END if
int arrayCount = CGPDFArrayGetCount( rectArray );
CGPDFReal coords[4];
for( int k = 0; k < arrayCount; ++k ) {
CGPDFObjectRef rectObj;
if(!CGPDFArrayGetObject(rectArray, k, &rectObj)) {
return;
} // END if
CGPDFReal coord;
if(!CGPDFObjectGetValue(rectObj, kCGPDFObjectTypeReal, &coord)) {
return;
} // END if
coords[k] = coord;
} // END for
Thanks for any help.
There is a PDF reader in source available here:
https://github.com/vfr/reader
It is on ObjectiveC and contains everything you need.
Related
Here is the scenario. I have an esp32, 2 led's and a ios example app I found online here. Currently If I press a button on my esp32 it notifies the ios app to display "1", if pressed again it displays "0". This works perfectly.
The tricky part is that this ios app allows me to send a write command to the esp32. I'd like to make it so if '1' is sent LED A turns ON and LED B turns OFF, then LED A OFF and LED B ON when 0 is sent. I am unable to do this though. Try as I might I can't figure out where in the chain of this project something is wrong. Maybe the code on the esp32 or maybe the app i'm unsure.
Here is my arduino code. (There is more to the code not mentioned, I actually have 4 led's but I only want to turn on 2 certain ones when a write command is sent).
#include <BLEDevice.h>
#include <BLEServer.h>
#include <BLEUtils.h>
#include <BLE2902.h>
BLEServer* pServer = NULL;
BLECharacteristic* pCharacteristic = NULL;
bool deviceConnected = false;
bool oldDeviceConnected = false;
boolean oldState = LOW;
uint32_t value = 0;
#define SERVICE_UUID "4fafc201-1fb5-459e-8fcc-c5c9c331914b"
#define CHARACTERISTIC_UUID "beb5483e-36e1-4688-b7f5-ea07361b26a8"
class MyServerCallbacks: public BLEServerCallbacks {
void onConnect(BLEServer* pServer) {
deviceConnected = true;
};
void onDisconnect(BLEServer* pServer) {
deviceConnected = false;
}
};
class MyCallbacks: public BLECharacteristicCallbacks {
void onWrite(BLECharacteristic *pCharacteristic) {
std::string rxValue = pCharacteristic->getValue();
if (rxValue.length() > 0) {
Serial.print("Received Value: ");
for (int i = 0; i < rxValue.length(); i++) {
Serial.print(rxValue[i]);
}
Serial.println();
if (rxValue.find("1") != -1) {
digitalWrite(13, HIGH);
digitalWrite(27, LOW);
}
else if (rxValue.find("0") != -1) {
digitalWrite(13, LOW);
digitalWrite(27, HIGH);
}
}
}
};
const int bt1 = 14;
boolean bt1g = true;
int bt1t = 0;
void setup() {
pinMode(13, OUTPUT);
pinMode(15, OUTPUT);
pinMode(33, OUTPUT);
pinMode(27, OUTPUT);
pinMode(bt1, INPUT_PULLUP);
Serial.begin(9600);
BLEDevice::init("ESP32");
pServer = BLEDevice::createServer();
pServer->setCallbacks(new MyServerCallbacks());
BLEService *pService = pServer->createService(SERVICE_UUID);
pCharacteristic = pService->createCharacteristic(
CHARACTERISTIC_UUID,
BLECharacteristic::PROPERTY_WRITE |
BLECharacteristic::PROPERTY_NOTIFY
);
pCharacteristic->addDescriptor(new BLE2902());
pService->start();
BLEAdvertising *pAdvertising = BLEDevice::getAdvertising();
pAdvertising->addServiceUUID(SERVICE_UUID);
pAdvertising->setScanResponse(false);
pAdvertising->setMinPreferred(0x0);
BLEDevice::startAdvertising();
Serial.println("Waiting a client connection to notify...");
}
void loop()
{
if (bt1g) {
if (digitalRead(bt1) == LOW ) {
bt1t = (bt1t + 1) % 2;
Serial.println(bt1t);
bt1g = false;
}
}
if (!bt1g) {
if (digitalRead(bt1) == HIGH) {
bt1g = true;
}
}
if (bt1t == 0) {
digitalWrite(15, LOW);
digitalWrite(33, HIGH);
}
}
boolean newState = digitalRead(15);
if (deviceConnected) {
if (newState != oldState) {
if (newState == LOW) {
pCharacteristic->setValue("1");
}
else {
pCharacteristic->setValue("0");
}
pCharacteristic->notify();
};
oldState = newState;
}
delay(50);
}
It looks like the entire code for the ios app is too long to submit to this post so here is the github
I'm really unsure and stuck in a rut. Any help is appreciated!
Could it be you are not discovering the correct characteristics? It looks like you only have one service and one characteristic.
The code below does compile, but it doesn't run as it should.
I'm not sure what am I doing wrong, so would someone be willing to tell me what I did wrong and what I should have done better.
What do I need to change to make it run properly?
#include<stdio.h>
#include<stdlib.h>
typedef struct sub_Node
{
int value;
struct sub_Node *next;
}sub_Node;
typedef struct Node
{
char *name;
struct Node *next;
struct sub_Node *sub_start;
}Node;
Node *start;
void add_player(char *name)
{
Node *temp;
temp = (Node *)malloc(sizeof(Node));
temp->next = start;
temp->name = name;
temp->sub_start = (sub_Node *)malloc(sizeof(sub_Node));
temp->sub_start->next = NULL;
temp->sub_start->value = -1;
start = temp;
}
void initialize()
{
char *p;
p = "\0";
add_player(p);
}
void remove_player(char *name)
{
Node *p;
for(p = start; p!= NULL; p = p->next)
if(p->name == name)
{
p->name = p->next->name;
p->next = p->next->next;
}
}
sub_Node* add_descending(sub_Node* sub_start, int piece_value)
{
sub_Node *temp, *prev, *next;
temp = (sub_Node *)malloc(sizeof(sub_Node));
temp->value = piece_value;
temp->next = NULL;
prev = NULL;
next = sub_start;
while(next && next->value >= piece_value)
{
prev = next;
next = next->next;
}
if(!next)
{
prev->next = temp;
}
else
{
if(prev)
{
temp->next = prev->next;
prev->next = temp;
}
else
{
temp->next = sub_start;
sub_start = temp;
}
}
return sub_start;
}
void add_piece(char *name, int piece_value)
{
Node *p;
int c;
for(p = start; p!=NULL; p = p->next)
if(p->name == name)
p->sub_start = add_descending(p->sub_start, piece_value);
}
void print_pieces(char *name)
{
Node *p;
sub_Node *q;
for(p = start; p!=NULL; p = p->next)
if(p->name == name)
{
printf("The values of the owned pieces are:");
for(q = p->sub_start; q->value != -1; q = q->next)
printf(" %d", q->value);
}
}
int lose_piece(char *name)
{
Node *p;
sub_Node *q;
int aux;
for(p = start; p!=NULL; p = p->next)
if(p->name == name)
{
for(q = p->sub_start; q->next->value != -1; q = q->next) {}
aux = q->value;
q->value = q->next->value;
q->next = q->next->next;
return aux;
}
}
void print_players()
{
Node *p;
printf("The players are: ");
for(p = start; p->name != "\0"; p = p->next)
printf("%s ", p->name);
printf("\n");
}
int main()
{
initialize();
int y, value;
char name[20];
printf("Insert a digit to execute the desired task:\n"
"<0> end the program\n"
"<1> add a player, who doesn't own any piece yet\n"
"<2> remove a player and all his pieces\n"
"<3> print the name of all the players\n"
"<4> a player gets a piece\n"
"<5> a player loses the piece with the lowest value out of the ones that he has\n"
"<6> prints the pieces of a player in a descending order by value\n\n");
do
{
printf("digit: ");
scanf("%d", &y);
switch(y)
{
case 1:
printf("Insert the player's name: ");
scanf("%s", name);
add_player(name);
break;
case 2:
printf("Insert the player's name: ");
scanf("%s", name);
remove_player(name);
break;
case 3:
print_players();
break;
case 4:
printf("Insert the player's name: ");
scanf("%s", name);
printf("Insert the value of the piece: ");
scanf("%d", value);
add_piece(name, value);
break;
case 5:
printf("Insert the player's name: ");
scanf("%s", name);
printf("\nThe player loses the piece: %d\n", lose_piece(name));
break;
case 6:
printf("Insert the player's name: ");
scanf("%s", name);
print_pieces(name);
}
} while(y != 0);
return 0;
}
your two main problems where this scanf("%d", value); value should be passed by reference like this scanf("%d", &value); and the second is string comparison in c as in your code p->name != "\0" and if(p->name == name) this is wrong because actually you are making comparison between addresses of strings (where it resides in memory) not strings values. to compare strings in c you have to use strcmp and families.
Actually 3 main problems. for setting string values as you did in temp->name = name; is little bit more complicated than that. because you are assigning to temp->name a string from the stack that is volatile (the stack will be more likely invalid soon you return from the function) . in your case you have to alloc a new string by using malloc (and friends) or just by using strdup.
here is as a bonus a slightly rewrite of your program, you will find many advises and is a good starting point for how to structure your code for an easy maintenance.
still want to advise you to change members and variables to more declarative names as in sub_start and sub_Node can be PieceNode and pieces respectively.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct sub_Node
{
int value;
struct sub_Node *next;
}sub_Node;
typedef struct Node
{
char *name;
struct Node *next;
struct Node *prev; // this to make life easyer
struct sub_Node *sub_start;
}Node;
Node *start = NULL;
Node *find_player(char *name){
Node *tmp = start;
while( tmp ){
if(strcmp(tmp->name,name) == 0 )
break;
tmp = tmp->next;
}
return tmp;
}
// int to return Error Code
//
int add_player(char *name)
{
Node *temp;
if( find_player(name)) {
printf("player %s already exists\n", name);
return 1;
}
// do not cast malloc
temp = malloc(sizeof(Node));
if( !temp ){
printf ("not enough memory\n");
return 2;
}
temp->name = strdup ( name); // here was your error
temp->sub_start = NULL; // keep it simple
temp->prev = NULL;
temp->next = start;
if(start)
start->prev = temp;
start = temp;
return 0; // no error
}
void DestroyPieces(sub_Node* piece){
if( piece ) {
DestroyPieces( piece->next );
free( piece );
}
}
// as usual use int to return error code
int remove_player(char *name)
{
Node *player = find_player(name);
if ( !player ){
return 1; // player not found
}
if ( player->next ){
player->next->prev = player->prev;
}
if ( player->prev ){
player->prev->next = player->next;
}
DestroyPieces(player->sub_start);
free(player->name);
free(player);
return 0; // success
}
sub_Node* new_piece(int value){
sub_Node *temp = malloc( sizeof(sub_Node) );
if(temp){
temp->value = value;
temp->next = NULL;
}
return temp;
}
// int to return error code
// pass sub_start as pointer to pointer, as it might be updated
int add_descending(sub_Node** psub_start, int piece_value)
{
sub_Node *piece, *current, *prev = NULL;
if( !psub_start){
return 5; // this should not happen
}
current = *psub_start;
piece = new_piece( piece_value );
if( !piece ) return 1; // no mem
if(!current){
// this is the first and only one
*psub_start = piece;
return 0; // OK
}
while(current && current->value >= piece_value)
{
prev = current;
current = current->next;
}
if( prev )
prev->next = piece;
piece->next = current;
if( current == *psub_start ){
*psub_start = piece;
}
return 0 ; // OK
}
void add_piece(Node * player, int piece_value)
{
if ( !player) {
return ;
}
if(add_descending (&(player->sub_start), piece_value) == 0 )
return ; //OK
printf("an error occured while adding a piece (%d) to player '%s'\n",piece_value,player->name);
}
void print_pieces(Node *player)
{
sub_Node *q;
if( !player ){
return;
}
if( !player->sub_start ){
printf("Player '%s' has no pieces\n",player->name);
return;
}
printf("The values of the owned pieces are:");
for(q = player->sub_start; q != NULL; q = q->next)
printf(" %d", q->value);
printf("\n");
}
void lose_piece(Node *player)
{
if( !player ){
return;
}
sub_Node *q, *prev = NULL;
int aux;
if( !player->sub_start ){
printf("Player '%s' has no pieces\n",player->name);
return;
}
// i think you want drop the last one
for(q = player->sub_start; q->next != NULL ;prev = q, q = q->next) {
;
}
if(prev)
prev->next = NULL;
else
player->sub_start = NULL;
aux = q->value;
free(q);
printf("\nThe player loses the piece: %d\n", aux);
return;
}
void print_players()
{
Node *p;
if( !start ){
printf("there are no players, try to add some\n");
return;
}
printf("The players are: ");
for(p = start; p != NULL; p = p->next)
printf("%s ", p->name);
printf("\n");
}
void print_menu(void){
printf("Insert a digit to execute the desired task:\n"
"<0> end the program\n"
"<1> add a player, who doesn't own any piece yet\n"
"<2> remove a player and all his pieces\n"
"<3> print the name of all the players\n"
"<4> a player gets a piece\n"
"<5> a player loses the piece with the lowest value out of the ones that he has\n"
"<6> prints the pieces of a player in a descending order by value\n\n");
}
Node * get_player(char *name){
Node *player = find_player(name);
if(!player)
printf("Player '%s' do not exists\n",name);
return player;
}
int main()
{
// initialize(); no more needed
int y, value;
char name[20];
Node *player;
print_menu();
do
{
printf("digit: ");
scanf("%d", &y);
switch(y)
{
case 1:
printf("Insert the player's name: ");
scanf("%s", name);
add_player(name);
break;
case 2:
printf("Insert the player's name: ");
scanf("%s", name);
player = get_player(name);
if( player )
break;
case 3:
print_players();
break;
case 4:
printf("Insert the player's name: ");
scanf("%s", name);
player = get_player(name);
if( player ){
printf("Insert the value of the piece: ");
scanf("%d", &value);
add_piece(player, value);
}
break;
case 5:
printf("Insert the player's name: ");
scanf("%s", name);
player = get_player(name);
lose_piece(player);
break;
case 6:
printf("Insert the player's name: ");
scanf("%s", name);
player = get_player(name);
print_pieces(player);
}
} while(y != 0);
return 0;
}
- (void)openPlayThreadWithRtmpURL:(NSString *)rtmpURL {
spx_int16_t *input_buffer;
do {
if (self.rtmpDelegate) {
[self.rtmpDelegate evenCallbackWithEvent:2000];
}
//init speex decoder and config;
speex_bits_init(&dbits);
dec_state = speex_decoder_init(&speex_wb_mode);
speex_decoder_ctl(dec_state, SPEEX_GET_FRAME_SIZE, &dec_frame_size);
input_buffer = malloc(dec_frame_size * sizeof(short));
NSLog(#"Init Speex decoder success frame_size = %d",dec_frame_size);
//init rtmp
pPlayRtmp = RTMP_Alloc();
RTMP_Init(pPlayRtmp);
NSLog(#"Play RTMP_Init %#\n", rtmpURL);
if (!RTMP_SetupURL(pPlayRtmp, (char*)[rtmpURL UTF8String])) {
NSLog(#"Play RTMP_SetupURL error\n");
if(self.rtmpDelegate) {
[self.rtmpDelegate evenCallbackWithEvent:2002];
}
break;
}
if (!RTMP_Connect(pPlayRtmp, NULL) || !RTMP_ConnectStream(pPlayRtmp, 0)) {
NSLog(#"Play RTMP_Connect or RTMP_ConnectStream error\n");
if(self.rtmpDelegate) {
[self.rtmpDelegate evenCallbackWithEvent:2002];
}
break;
}
if(self.rtmpDelegate) {
[self.rtmpDelegate evenCallbackWithEvent:2001];
}
NSLog(#"Player RTMP_Connected \n");
RTMPPacket rtmp_pakt = {0};
isStartPlay = YES;
while (isStartPlay && RTMP_ReadPacket(pPlayRtmp, &rtmp_pakt)) {
if (RTMPPacket_IsReady(&rtmp_pakt)) {
if (!rtmp_pakt.m_nBodySize) {
continue;
}
if (rtmp_pakt.m_packetType == RTMP_PACKET_TYPE_AUDIO) {
NSLog(#"Audio size = %d head = %d time = %d", rtmp_pakt.m_nBodySize, rtmp_pakt.m_body[0], rtmp_pakt.m_nTimeStamp);
speex_bits_read_from(&dbits, rtmp_pakt.m_body + 1, rtmp_pakt.m_nBodySize - 1);
speex_decode_int(dec_state, &dbits, input_buffer); //audioData in the input_buffer
//do something...
} else if (rtmp_pakt.m_packetType == RTMP_PACKET_TYPE_VIDEO) {
// 处理视频数据包
} else if (rtmp_pakt.m_packetType == RTMP_PACKET_TYPE_INVOKE) {
// 处理invoke包
NSLog(#"RTMP_PACKET_TYPE_INVOKE");
RTMP_ClientPacket(pPlayRtmp,&rtmp_pakt);
} else if (rtmp_pakt.m_packetType == RTMP_PACKET_TYPE_INFO) {
// 处理信息包
//NSLog(#"RTMP_PACKET_TYPE_INFO");
} else if (rtmp_pakt.m_packetType == RTMP_PACKET_TYPE_FLASH_VIDEO) {
// 其他数据
int index = 0;
while (1) {
int StreamType; //1-byte
int MediaSize; //3-byte
int TiMMER; //3-byte
int Reserve; //4-byte
char* MediaData; //MediaSize-byte
int TagLen; //4-byte
StreamType = rtmp_pakt.m_body[index];
index += 1;
MediaSize = bigThreeByteToInt(rtmp_pakt.m_body + index);
index += 3;
TiMMER = bigThreeByteToInt(rtmp_pakt.m_body + index);
index += 3;
Reserve = bigFourByteToInt(rtmp_pakt.m_body + index);
index += 4;
MediaData = rtmp_pakt.m_body + index;
index += MediaSize;
TagLen = bigFourByteToInt(rtmp_pakt.m_body + index);
index += 4;
//NSLog(#"bodySize:%d index:%d",rtmp_pakt.m_nBodySize,index);
//LOGI("StreamType:%d MediaSize:%d TiMMER:%d TagLen:%d\n", StreamType, MediaSize, TiMMER, TagLen);
if (StreamType == 0x08) {
//音频包
//int MediaSize = bigThreeByteToInt(rtmp_pakt.m_body+1);
// LOGI("FLASH audio size:%d head:%d time:%d\n", MediaSize, MediaData[0], TiMMER);
speex_bits_read_from(&dbits, MediaData + 1, MediaSize - 1);
speex_decode_int(dec_state, &dbits, input_buffer);
//[mAudioPlayer putAudioData:input_buffer];
// putAudioQueue(output_buffer,dec_frame_size);
} else if (StreamType == 0x09) {
//视频包
// LOGI( "video size:%d head:%d\n", MediaSize, MediaData[0]);
}
if (rtmp_pakt.m_nBodySize == index) {
break;
}
}
}
RTMPPacket_Free(&rtmp_pakt);
}
}
if (isStartPlay) {
if(self.rtmpDelegate) {
[self.rtmpDelegate evenCallbackWithEvent:2005];
}
isStartPlay = NO;
}
} while (0);
[mAudioPlayer stopPlay];
if (self.rtmpDelegate) {
[self.rtmpDelegate evenCallbackWithEvent:2004];
}
if (RTMP_IsConnected(pPlayRtmp)) {
RTMP_Close(pPlayRtmp);
}
RTMP_Free(pPlayRtmp);
free(input_buffer);
speex_bits_destroy(&dbits);
speex_decoder_destroy(dec_state);
}
This is my custom method. RtmpURL is a NSString'S object, it is a stream server address. Use this method, I can get the encoded of audio stream from the server, after that, I use speex decoder to decode the data that I got, just like this:
//init speex decoder and config;
speex_bits_init(&dbits);
dec_state = speex_decoder_init(&speex_wb_mode);
speex_decoder_ctl(dec_state, SPEEX_GET_FRAME_SIZE, &dec_frame_size);
input_buffer = malloc(dec_frame_size * sizeof(short));
NSLog(#"Init Speex decoder success frame_size = %d",dec_frame_size);
if (rtmp_pakt.m_packetType == RTMP_PACKET_TYPE_AUDIO) {
NSLog(#"Audio size = %d head = %d time = %d", rtmp_pakt.m_nBodySize, rtmp_pakt.m_body[0], rtmp_pakt.m_nTimeStamp);
speex_bits_read_from(&dbits, rtmp_pakt.m_body + 1, rtmp_pakt.m_nBodySize - 1);
speex_decode_int(dec_state, &dbits, input_buffer); //audioData in the input_buffer
//do something...
}
Now, decoded of audio data are stored in the input_buffer, and this is my confusion. How do I use the AudioUnit to play the audio data.And this is my playback callback function:
OSStatus playCallback(void *inRefCon,
AudioUnitRenderActionFlags *ioActionFlags,
const AudioTimeStamp *inTimeStamp,
UInt32 inBusNumber,
UInt32 inNumberFrames,
AudioBufferList *ioData){
AudioPlayer *THIS = (__bridge AudioPlayer *)inRefCon;
//How do I use the AudioUnit to play the audio stream from server?
return noErr;
}
I hope some friends to solve my confusion, if you were used the audioUnit, Thank you so much!
In your playCallback, you need to copy the audio into the buffer ioData.
For example
memcpy (ioData->mBuffers[0].mData, input_buffer + offset, numBytes );
// increase offset based on how many frames it requests.
The input variable inNumberFrames is the number of frames that it is ready for. This might be less than the number of frames in input_buffer. So you need to keep track of your play position.
I do not know your audio format this specified in your audio stream basic description. You need to calculate how many bytes need copied considering mono/stereo, number of bytes per channel, and of course inNumberFrames.
There are some very good resources here link
Need some help with reading in lines of data from a text file using the fgets and string tokenization commands, which will then be used to create a linked list. I've followed some examples I've found on Stack Overflow and other tutorial websites, but still cannot get the read function below to work properly in my program, it just causes it to crash. The data file has lines like this:
Zucchini, Squash, pound, 2.19, 45
Yellow, Squash, pound, 1.79, 15
Based on everything I've read, I believe I have the necessary code, but obviously I'm missing something. Also, I commented out one of the fields (the one for float price) as I'm not sure what to use to copy the float value from the data, as I cannot treat it as a string (the integer value right below it seems to let me get away with it in my compiler).
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
// Struct for linked list node
struct produceItem
{
char produce[20];
char type[20];
char soldBy[20];
float price;
int quantityInStock;
struct produceItem *next;
};
// Function to read in data from file to
void read(struct produceItem **head)
{
struct produceItem *temp = NULL;
struct produceItem *right = NULL;
//char ch[3];
char line[50];
char *value;
FILE *data = fopen("RecitationFiveInput.txt", "r");
printf("Trying to open file RecitationFiveInput.txt\n");
if (data == NULL)
{
printf("Could not open file RecitationFiveInput.txt\n");
}
else
{
while(fgets(line, sizeof(line), data))
{
value = strtok(line, ", ");
strcpy(temp->produce, strdup(value));
value = strtok(NULL, ", ");
strcpy(temp->type, strdup(value));
value = strtok(NULL, ", ");
strcpy(temp->soldBy, strdup(value));
//value = strtok(NULL, ", ");
//strcpy(temp->price, strdup(value));
value = strtok(NULL, " \n");
strcpy(temp->quantityInStock, strdup(value));
temp->next = NULL;
if (*head == NULL)
{
*head = temp;
}
else
{
right = *head;
while(right->next != NULL)
{
right = right->next;
}
right->next = temp;
}
}
printf("Successfully opened file RecitationFiveInput.txt\n");
}
fclose(data);
return;
}
// Function to display the nodes of the linked list that contains the data from the data file
void display(struct produceItem *head)
{
int value = 1;
struct produceItem *temp = NULL;
temp = head;
printf("=============================================================================\n");
printf(" Item # Produce Type Sold By Price In Stock\n");
printf("=============================================================================\n");
if(temp == NULL)
{
return;
}
else
{
while(temp != NULL)
{
printf(" %d %s %s %s %lf %d\n", value, temp->produce, temp->type, temp->soldBy, temp->price, temp->quantityInStock);
value++;
temp = temp->next;
if(temp == NULL)
{
break;
}
}
}
return;
}
//Main function
int main()
{
int input = 0;
struct produceItem *head = NULL;
while(1)
{
printf("\nList Operations\n");
printf("=================\n");
printf("1. Stock Produce Department\n");
printf("2. Display Produce Inventory\n");
printf("3. Reverse Order of Produce Inventory\n");
printf("4. Export Produce Inventory\n");
printf("5. Exit Program\n");
printf("Enter your choice: ");
if(scanf("%d", &input) <= 0)
{
printf("Enter only an integer.\n");
exit(0);
}
else
{
switch(input)
{
case 1:
read(&head);
break;
case 2:
display(head);
break;
case 3:
//function
break;
case 4:
//function
break;
case 5:
printf("You have exited the program, Goodbye!\n");
return 0;
break;
default:
printf("Invalid option.\n");
}
}
}
return 0;
}
Never mind everyone, found the issue. The crashes were due to me not allocating memory for the temp pointer in the read me function.
I have a requirement to parse data files in "txf" format. The files may contain more than 1000 entries. Since the format is well defined like JSON, I wanted to make a generic parser like JSON, which can serialise and deserialise txf files.
On contrary to JSON, the mark up doesn't have a way to identify an object or an array. If an entry with same tag occurs, we need to consider it as an array.
# Marks the start of an object.
$ Marks the members of an object
/ Marks the end of an object
Following is a sample "txf" file
#Employees
$LastUpdated=2015-02-01 14:01:00
#Employee
$Id=1
$Name=Employee 01
#Departments
$LastUpdated=2015-02-01 14:01:00
#Department
$Id=1
$Name=Department Name
/Department
/Departments
/Employee
#Employee
/Employee
/Employees
I was able to create a generic TXF Parser using NSScanner. But with more entries the performance needs more tweaking.
I wrote the foundation object obtained as plist and compared its performance again the parser I wrote. My parser is around 10 times slower than plist parser.
While plist file size is 5 times more than txf and has more markup characters, I feel that there is a lot of room for optimization.
Any help in that direction is highly appreciated.
EDIT : Including the parsing code
static NSString *const kArray = #"TXFArray";
static NSString *const kBodyText = #"TXFText";
#interface TXFParser ()
/*Temporary variable to hold values of an object*/
#property (nonatomic, strong) NSMutableDictionary *dict;
/*An array to hold the hierarchial data of all nodes encountered while parsing*/
#property (nonatomic, strong) NSMutableArray *stack;
#end
#implementation TXFParser
#pragma mark - Getters
- (NSMutableArray *)stack{
if (!_stack) {
_stack = [NSMutableArray new];
}return _stack;
}
#pragma mark -
- (id)objectFromString:(NSString *)txfString{
[txfString enumerateLinesUsingBlock:^(NSString *string, BOOL *stop) {
if ([string hasPrefix:#"#"]) {
[self didStartParsingTag:[string substringFromIndex:1]];
}else if([string hasPrefix:#"$"]){
[self didFindKeyValuePair:[string substringFromIndex:1]];
}else if([string hasPrefix:#"/"]){
[self didEndParsingTag:[string substringFromIndex:1]];
}else{
//[self didFindBodyValue:string];
}
}]; return self.dict;
}
#pragma mark -
- (void)didStartParsingTag:(NSString *)tag{
[self parserFoundObjectStartForKey:tag];
}
- (void)didFindKeyValuePair:(NSString *)tag{
NSArray *components = [tag componentsSeparatedByString:#"="];
NSString *key = [components firstObject];
NSString *value = [components lastObject];
if (key.length) {
self.dict[key] = value?:#"";
}
}
- (void)didFindBodyValue:(NSString *)bodyString{
if (!bodyString.length) return;
bodyString = [bodyString stringByTrimmingCharactersInSet:[NSCharacterSet illegalCharacterSet]];
if (!bodyString.length) return;
self.dict[kBodyText] = bodyString;
}
- (void)didEndParsingTag:(NSString *)tag{
[self parserFoundObjectEndForKey:tag];
}
#pragma mark -
- (void)parserFoundObjectStartForKey:(NSString *)key{
self.dict = [NSMutableDictionary new];
[self.stack addObject:self.dict];
}
- (void)parserFoundObjectEndForKey:(NSString *)key{
NSDictionary *dict = self.dict;
//Remove the last value of stack
[self.stack removeLastObject];
//Load the previous object as dict
self.dict = [self.stack lastObject];
//The stack has contents, then we need to append objects
if ([self.stack count]) {
[self addObject:dict forKey:key];
}else{
//This is root object,wrap with key and assign output
self.dict = (NSMutableDictionary *)[self wrapObject:dict withKey:key];
}
}
#pragma mark - Add Objects after finding end tag
- (void)addObject:(id)dict forKey:(NSString *)key{
//If there is no value, bailout
if (!dict) return;
//Check if the dict already has a value for key array.
NSMutableArray *array = self.dict[kArray];
//If array key is not found look for another object with same key
if (array) {
//Array found add current object after wrapping with key
NSDictionary *currentDict = [self wrapObject:dict withKey:key];
[array addObject:currentDict];
}else{
id prevObj = self.dict[key];
if (prevObj) {
/*
There is a prev value for the same key. That means we need to wrap that object in a collection.
1. Remove the object from dictionary,
2. Wrap it with its key
3. Add the prev and current value to array
4. Save the array back to dict
*/
[self.dict removeObjectForKey:key];
NSDictionary *prevDict = [self wrapObject:prevObj withKey:key];
NSDictionary *currentDict = [self wrapObject:dict withKey:key];
self.dict[kArray] = [#[prevDict,currentDict] mutableCopy];
}else{
//Simply add object to dict
self.dict[key] = dict;
}
}
}
/*Wraps Object with a key for the serializer to generate txf tag*/
- (NSDictionary *)wrapObject:(id)obj withKey:(NSString *)key{
if (!key ||!obj) {
return #{};
}
return #{key:obj};
}
EDIT 2:
A sample TXF file with more than 1000 entries.
Have you considered using pull-style reads & recursive processing? That would eliminate reading the whole file into memory and also eliminate managing some own stack to keep track how deep you're parsing.
Below an example in Swift. The example works with your sample "txf", but not with the dropbox version; some of your "members" span over multiple lines. If this is a requirement, it can easily be implemented into switch/case "$" section. However, I don't see your own code handling this either. Also, the example doesn't follow the correct Swift error handling yet (the parse method would need an additional NSError parameter)
import Foundation
extension String
{
public func indexOfCharacter(char: Character) -> Int? {
if let idx = find(self, char) {
return distance(self.startIndex, idx)
}
return nil
}
func substringToIndex(index:Int) -> String {
return self.substringToIndex(advance(self.startIndex, index))
}
func substringFromIndex(index:Int) -> String {
return self.substringFromIndex(advance(self.startIndex, index))
}
}
func parse(aStreamReader:StreamReader, parentTagName:String) -> Dictionary<String,AnyObject> {
var dict = Dictionary<String,AnyObject>()
while let line = aStreamReader.nextLine() {
let firstChar = first(line)
let theRest = dropFirst(line)
switch firstChar! {
case "$":
if let idx = theRest.indexOfCharacter("=") {
let key = theRest.substringToIndex(idx)
let value = theRest.substringFromIndex(idx+1)
dict[key] = value
} else {
println("no = sign")
}
case "#":
let subDict = parse(aStreamReader,theRest)
var list = dict[theRest] as? [Dictionary<String,AnyObject>]
if list == nil {
dict[theRest] = [subDict]
} else {
list!.append(subDict)
}
case "/":
if theRest != parentTagName {
println("mismatch... [\(theRest)] != [\(parentTagName)]")
} else {
return dict
}
default:
println("mismatch... [\(line)]")
}
}
println("shouldn't be here...")
return dict
}
var data : Dictionary<String,AnyObject>?
if let aStreamReader = StreamReader(path: "/Users/taoufik/Desktop/QuickParser/QuickParser/file.txf") {
if var line = aStreamReader.nextLine() {
let tagName = line.substringFromIndex(advance(line.startIndex, 1))
data = parse(aStreamReader, tagName)
}
aStreamReader.close()
}
println(JSON(data!))
And the StreamReader was borrowed from https://stackoverflow.com/a/24648951/95976
Edit
see full code https://github.com/tofi9/QuickParser
pull-style line-by-line read in objective-c: How to read data from NSFileHandle line by line?
Edit 2
I rewrote the above in C++11 and got it to run in less than 0.05 seconds (release mode) on a 2012 MBA I5 using the updated file on dropbox. I suspect NSDictionary and NSArray must have some penalty. The code below can be compiled into an objective-c project (file needs have extension .mm):
#include <iostream>
#include <sstream>
#include <string>
#include <fstream>
#include <map>
#include <vector>
using namespace std;
class benchmark {
private:
typedef std::chrono::high_resolution_clock clock;
typedef std::chrono::milliseconds milliseconds;
clock::time_point start;
public:
benchmark(bool startCounting = true) {
if(startCounting)
start = clock::now();
}
void reset() {
start = clock::now();
}
double elapsed() {
milliseconds ms = std::chrono::duration_cast<milliseconds>(clock::now() - start);
double elapsed_secs = ms.count() / 1000.0;
return elapsed_secs;
}
};
struct obj {
map<string,string> properties;
map<string,vector<obj>> subObjects;
};
obj parse(ifstream& stream, string& parentTagName) {
obj obj;
string line;
while (getline(stream, line))
{
auto firstChar = line[0];
auto rest = line.substr(1);
switch (firstChar) {
case '$': {
auto idx = rest.find_first_of('=');
if (idx == -1) {
ostringstream o;
o << "no = sign: " << line;
throw o.str();
}
auto key = rest.substr(0,idx);
auto value = rest.substr(idx+1);
obj.properties[key] = value;
break;
}
case '#': {
auto subObj = parse(stream, rest);
obj.subObjects[rest].push_back(subObj);
break;
}
case '/':
if(rest != parentTagName) {
ostringstream o;
o << "mismatch end of object " << rest << " != " << parentTagName;
throw o.str();
} else {
return obj;
}
break;
default:
ostringstream o;
o << "mismatch line " << line;
throw o.str();
break;
}
}
throw "I don't know why I'm here. Probably because the file is missing an end of object marker";
}
void visualise(obj& obj, int indent = 0) {
for(auto& property : obj.properties) {
cout << string(indent, '\t') << property.first << " = " << property.second << endl;
}
for(auto& subObjects : obj.subObjects) {
for(auto& subObject : subObjects.second) {
cout << string(indent, '\t') << subObjects.first << ": " << endl;
visualise(subObject, indent + 1);
}
}
}
int main(int argc, const char * argv[]) {
try {
obj result;
benchmark b;
ifstream stream("/Users/taoufik/Desktop/QuickParser/QuickParser/Members.txf");
string line;
if (getline(stream, line))
{
string tagName = line.substr(1);
result = parse(stream, tagName);
}
cout << "elapsed " << b.elapsed() << " ms" << endl;
visualise(result);
}catch(string s) {
cout << "error " << s;
}
return 0;
}
Edit 3
See link for full code C++: https://github.com/tofi9/TxfParser
I did some work on your github source - with following 2 changes I got overal improvement of 30% though the major improvement is from "Optimisation 1"
Optimisation 1 - based on your data came with with following work.
+ (int)locate:(NSString*)inString check:(unichar) identifier
{
int ret = -1;
for (int i = 0 ; i < inString.length; i++){
if (identifier == [inString characterAtIndex:i]) {
ret = i;
break;
}
}
return ret;
}
- (void)didFindKeyValuePair:(NSString *)tag{
#if 0
NSArray *components = [tag componentsSeparatedByString:#"="];
NSString *key = [components firstObject];
NSString *value = [components lastObject];
#else
int locate = [TXFParser locate:tag check:'='];
NSString *key = [tag substringToIndex:locate];
NSString *value = [tag substringFromIndex:locate+1];
#endif
if (key.length) {
self.dict[key] = value?:#"";
}
}
Optimisation 2:
- (id)objectFromString:(NSString *)txfString{
[txfString enumerateLinesUsingBlock:^(NSString *string, BOOL *stop) {
#if 0
if ([string hasPrefix:#"#"]) {
[self didStartParsingTag:[string substringFromIndex:1]];
}else if([string hasPrefix:#"$"]){
[self didFindKeyValuePair:[string substringFromIndex:1]];
}else if([string hasPrefix:#"/"]){
[self didEndParsingTag:[string substringFromIndex:1]];
}else{
//[self didFindBodyValue:string];
}
#else
unichar identifier = ([string length]>0)?[string characterAtIndex:0]:0;
if (identifier == '#') {
[self didStartParsingTag:[string substringFromIndex:1]];
}else if(identifier == '$'){
[self didFindKeyValuePair:[string substringFromIndex:1]];
}else if(identifier == '/'){
[self didEndParsingTag:[string substringFromIndex:1]];
}else{
//[self didFindBodyValue:string];
}
#endif
}]; return self.dict;
}
Hope it helps you.