C :: Way To Free Unsigned Pointer Array In Best Way
Feb 24, 2013
how is the best way to free unsigned pointer array allocated with cmallc?
Code:
uint8_t *buf;
buf = cs_calloc(ca->len + 13);
i do like this , but i know this is not quite right , since i got compile warning passing argument 1 of ‘free’ makes pointer from integer without a cast
Code:
for (i = 0; i < ca->len + 13; i++)
{
free(buf[i]);
buf[i] = NULL;
}
free(buf); do i need to free each element of array like above?
An attempt to create a class which is basically a mimic of vector<int> i don't seem to know how to delete pointer x in a destructor to free memory, also on pushback and pushfront methods, i can't free y when i implement delete[] y; y=NULL; i get some NULL out put when cout 'ing the object in main, why is that happening and how do i free memory y.
#include<iostream> using namespace std; class vectorOfint{ int* x; int size; public: vectorOfint();
Goal: To allocate some memory as a char*, read in some binary data, re-interpret it as a float* and then free the memory.
My code looks like:
void someFunction(float* &result) { char * tmp = new char[1000]; //...Fill the char buffer here... result = (float*)tmp; //Reinterpret binary data as floats
[Code] ....
Is the cast back to char* necessary on the red line (or could I have validly left it as float*)? Would it be different if I had written char * tmp = (char*)malloc(sizeof(char)*1000); on the blue line (and correspondingly used free (char*)floatData on the red line?
I came across some code and it's not clear why it is casting an unsigned char * to another pointer type only to free it right after. Here are the relevant structures:
As you can see, _Edge_Message has a *msg field, but in the function below, they cast it to the other two structure types inside the case blocks of the switch statement only to free it. What is the point or advantage of doing this?
Code: void _edje_message_free(Edje_Message *em) { if (em->msg) { int i; switch (em->type) {
Now i want to convert this into a unsigned char pointer.
unsigned char * pBMPHeaderData;
I already got the raw image data in another unsigned char buffer.
unsigned char* pRawBMPData;
Now i want to make a complete BMP image by adding the header info and raw data into a new unsigned char pointer. For this i need to convert the BITMAPINFO struct into a unsigned char *
How can i write a function that will read an "unsigned integer" into a variable of type "unsigned short int"? i can not use cin >> inside the function.. so i am looking for atleast a hint!
Having some frustrating issues trying to free memory from a dynamically allocated array of pointers to linked lists. I think the problem is in how I initialize the pointers to NULL. Is there a more elegant way to have the program recognize that the list is empty so it knows to create a head node for the linked list in the function 'add_end_stub_to_array'?
I ran the code through Valgrind and it says that memory is definitely lost from this array.
This is the structure definition.
Code: struct stub_edge { int loc_id; int anim_type; int mkt; struct stub_edge *next_node; };
Here is the code snippet from main allocating and deallocating memory to the array.
Here the function for adding nodes to the lists by reading through a dynamically allocated 2D array. (The end_stubs array is ordered by month and each linked list represents events occuring within the month).
Code:
struct stub_edge **add_end_stub_to_array(int **end_stubs, struct stub_edge **list) { long int i = 0; int mon = 0; struct stub_edge *current_node1; struct stub_edge *new_node1; int break1 = 0; while(i < num_edges && break1 == 0 && mon < 12)
[Code]...
Here is the function for freeing memory from the list.
I am having some trouble performing this. I am not sure, if my unsigned char arrays are null terminated, but I don't think so. Here is my code: They are supposed to be byte arrays of size 16.
int setkey(unsigned char* ky) { printf("INSIDE POLY-DEL ... key byte array passed in HEX: "); int i; for (i = 0; i < (int)16; i++)
I am trying to write down in binary format an array of unsigned int values but i get the following compilation error :
: In function ‘int CIndex(std::fstream&, std::fstream&, std::fstream&, std::fstream&)’: ./src/IndexBuilder/index.cpp:23:26: error: no matching function for call to ‘std::basic_fstream<char>::write(int*, long unsigned int)’ ./src/IndexBuilder/index.cpp:23:26: note: candidate is: /usr/include/c++/4.6/bits/ostream.tcc:184:5: note: std::basic_ostream<_CharT, _Traits>& std::basic_ostream<_CharT, _Traits>::write(const _CharT*, std::streamsize) [with _CharT = char, _Traits = std::char_traits<char>, std::streamsize = long int]
This is the part the is not working:
Code: // uia is : unsigned int * uia; // then I have allocated the space for it // load it with unsigned int's // k is the number of variables in my array
o.write(uia,sizeof(unsigned int)*k); But thsi should be so simple and strait forward.... in c i do it as :
Code: fwrite(uia, sizeof(unsigned int), k , fp); but since i would need to convert fstream to FILE* i decided to do it c++ way.
I have an embedded microcontroller system communicating with a similar system by radio. The api for the radio requires data to be transmitted as an unsigned char array. It will always transmit a positive integer in the range 0 to 255.When I receive the data I am having difficult in extracting this positive integer.
Code: unsigned char rxData[4]={'1','2','3',''}; int inVal=0;
//want to assign inVal whatever number was transmitted
E.g. 123
I've been at this for a week and have tried at least 10 different approaches including the use of the atoi(), copying the absolute value of each element of rxData into another char array, reinterpret_cast, and others.
I need fastest method to reverse order of bytes in my char array.
For example i have:
unsigned char buf[8]; // consider data stored in buf is 88 77 66 55 44 33 22 11 // how to reverse it to: 11 22 33 44 55 66 77 88 // currently i can do it by equal assignment , i make another buf like: unsigned char buf_ok[8];
[Code] ....
// This does reverse the bytes as i want but its very slow , i am looking for fast method ..
Where col is a 'vec4' struct with a double[4] with values between 0 and 1 (this is checked and clamped elsewhere, and the output is safely within bounds). This is basically used to store rgb and intensity values.
Now, when I add a constant integer as a pixel value, i.e.:
buffer_rgb[i] = ((unsigned char)255;
Everything works as it should. However, when I use the above code, where col is different for every sample sent to the buffer, the resulting image becomes skewed in a weird way, as if the buffer writing is becoming offset as it goes.
You can see in the 'noskew' image all pixels are the same value, from just using an unchanging int to set them. It seems to work with any value between 0-255 but fails only when this value is pulled from my changing col array.
Whole function is here:
// adds sample to pixel. coordinates must be between (-1,1) void Frame::addSample(vec4 col, double contrib, double x, double y) { if (x < -1 || x >= 1 || y < -_aaspect || y >= _aaspect) {
So I wrote a program to turn a binary file's data into an unsigned character array for inclusion in an executable. It works just super.
I'm wondering how I can write a program that will perform this operation on every file in a directory and all it's sub-directories so that I can I can include everything I need all at ounce.
i have been fiddling with pointers but I don't understand how the proper syntax is written when I want to acces an element of an array through a pointer to a pointer...The code is all mostly just random bs for learning purposes. I marked the problem "// THIS LINE"
This is a sample program that declares a Matrix as a structure with an array as a pointer to a pointer. The following program is supposed to store a matrix in the structure "_Matrix" and later print the matrix just entered but it fails giving me a "segmentation fault". The sample code is given below
Code: #include <stdio.h> #include <stdlib.h> struct _Matrix { int row_size; int col_size; int **mat;
I am trying to assign the integer value to unsigned char array. But it is not storing the integer values. It prints the ascii values. Here the code snippet
The values which are stored in uc[] is ascii values.I need the integer values to be stored in uc[]. I tried to do it with sprintf. but the output is not as expected. if I print the uc[i] it should diplay the value as 0,1,2....99.
Example radix sort function to sort an array of 64 bit unsigned integers. To allow for variable bin sizes, the array is scanned one time to create a matrix of 8 histograms of 256 counts each, corresponding to the number of instances of each possible 8 bit value in the 8 bytes of each integer, and the histograms are then converted into indices by summing the histograms counts. Then a radix sort is performed using the matrix of indices, post incrementing each index as it is used.
Code: typedef unsigned long long UI64; typedef unsigned long long *PUI64; PUI64 RadixSort(PUI64 pData, PUI64 pTemp, size_t count) { size_t mIndex[8][256] = {0}; /* index matrix */ PUI64 pDst, pSrc, pTmp; size_t i,j,m,n; UI64 u;
I wish to know how to traverse or loop through a dynamic 2D array using pointer to pointer as returned by the code above. Like I would in a static T[20][20] 2D array.
I am having problems copying outputs of the above code into other unsigned char other[32]. I need to keep the output of dev/urandom for backup. But, when I try to assign the values by memcpy(other, key, 32), the values do not match. The same problem happens by assigning values index by index in a loop.
Let say h(0)=01 and h(1)=10 and let say our first string is w=0 h(w)=01, h^2(w)=0110 h^3(w)=01101001..etc.
We have used h map, which is given in the program comment statement. Same thing, program is doing for three letters. These three letters we have passed as argument in h_i function. e.g. h_i(2,w,"a","d","g") function will apply the 3 letter map h(definition is given in commented form in program) 2 times on string w.
In program w=a; and three letters are a, d and g. /* h(a)=abcab,h(b)=acabcb,h(c)=acbcacb */ here b=d and c=g.
Above program gives core dump at free(w2) free(w1). if we remove these free statements then it gives correct answer. But, we want to free w1 and w2 in the above code. How can we make free both w1 and w2 strings?
I'm trying to free allocated memory for structure. It seems like free() gets only pointer and not regular types . my question is basic and simple – is passing pointer to free() frees the pointer or the variable it points at? or both?
I don't use Visual Studio and/or C++ so I would like to do it without them. I found this article c++ - How to determine CPU and memory consumption from inside a process? - Stack Overflow
I tried some lines of code but no one works for me.
