char<->int->escape, C (clang)

Language: Layout:

//clang 3.8.0
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <inttypes.h>
#include <string.h>
#include <time.h>
#include <sys/timeb.h>

char * str_escape(char str[])
{
	/*
		//To escape a single character, do this:
		char x = '\t'; //not a string - character
		char x2[256];	//temp variable to save character
		sprintf(x2, "%c", x);//write character as string
	    puts(str_escape(x2));//escape this...
	*/
    char chr[3];
    char *buffer = malloc(sizeof(char));
	//chr[3] = '\0';
	memset(buffer, 0, sizeof(*buffer));
	//memset(buffer, '\0', sizeof(buffer));
    unsigned int len = 1, blk_size;
	//printf("BUFFER %s", buffer);
	
    while (*str != '\0') {
        blk_size = 2;
        switch (*str) {
            case '\n':
                strcpy(chr, "\\n");
                break;
            case '\t':
                strcpy(chr, "\\t");
                break;
            case '\v':
                strcpy(chr, "\\v");
                break;
            case '\f':
                strcpy(chr, "\\f");
                break;
            case '\a':
                strcpy(chr, "\\a");
                break;
            case '\b':
                strcpy(chr, "\\b");
                break;
            case '\r':
                strcpy(chr, "\\r");
                break;
            case '\?':
                strcpy(chr, "\\?");
                break;
            case '\'':
				blk_size = 3;
                strcpy(chr, "\\\'");
                break;
            case '\"':
				blk_size = 3;
                strcpy(chr, "\\\"");
                break;
            case '\\':
				blk_size = 3;
                strcpy(chr, "\\\\");
                break;
            default:
				//printf("default switch\n");
                sprintf(chr, "%c", *str);
                blk_size = 1;
                break;
        }
        len += blk_size;
        buffer = realloc(buffer, len * sizeof(char));
        strcat(buffer, chr);
        ++str;
    }
    return buffer;
}

int main(void)
{
    char x = '\t';
    char x2[256];
    sprintf(x2, "%c", x);
    puts(str_escape(x2));
    puts(str_escape("\tAnbms\n"));
    puts(str_escape("\tA\v\fZ\a"));
    puts(str_escape("txt \t\n\r\f\a\v 1 \t\n\r\f\a\v tt"));
    puts(str_escape("dhsjdsdjhs hjd hjds "));
    puts(str_escape(""));
    puts(str_escape("0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!\"#$%&\'()*+,-./:;<=>?@[\\]^_`{|}~ \t\n\r\f\a\v"));
    puts(str_escape("\x0b\x0c\t\n\r\f\a\v"));
    puts(str_escape("\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f\x10\x11\x12\x13\x14"));
    
    
    //codes                      34  39    92    9  10  13  12  07  11  63  92
    //unescaped characters:      "    '     \   \t  \n  \r  \f  \a  \v  \?  \b
    //escaped characters:		\"   \'    \\   \t  \n  \r  \f  \a  \v  \?  \b
    
    //multichar associative array
    char *ecsape[128] = {
        "\0",    "\1",    "\2",    "\3",    "\4",    "\5",    "\6",    "\\a\0", "\\b\0",   "\\t\0",
        "\\n\0", "\\v\0", "\\f\0", "\\r\0", "\14",   "\15",   "\16",   "\17",   "\18",     "\19",
        "\20",   "\21",   "\22",   "\23",   "\24",   "\25",   "\26",   "\27",   "\28",     "\29",
        "\30",   "\31",   "\32",   "\33",   "\"\0",  "\35",   "\36",   "\37",   "\38",     "\\'\0",
        "\40",   "\41",   "\42",   "\43",   "\44",   "\45",   "\46",   "\47",   "\48",     "\49",
        "\50",   "\51",   "\52",   "\53",   "\54",   "\55",   "\56",   "\57",   "\58",     "\59",
        "\60",   "\61",   "\62",   "\\?\0", "\64",   "\65",   "\66",   "\67",   "\68",     "\69",
        "\70",   "\71",   "\72",   "\73",   "\74",   "\75",   "\76",   "\77",   "\78",     "\79",
        "\80",   "\81",   "\82",   "\83",   "\84",   "\85",   "\86",   "\87",   "\88",     "\89",
        "\90",   "\91",   "\\\0",  "\93",   "\94",   "\95",   "\96",   "\97",   "\98",     "\99",
    };
    
    printf("\n\n");
    
    char vopros = '?';                               //single char
    printf("%c - %s\n", vopros, ecsape[vopros]);     //from variable
    int tab_code = 9;                                //char as charcode int
    printf("%c - %s\n", tab_code, ecsape[tab_code]); //from variable
    printf("%c - %s\n", "\""[0], ecsape["\""[0]]);   //escaped string
    printf("%c - %s\n", '"', ecsape['"']);           //unescaped string char ''

int char_code_as_string = "92";
    int char_code = atoi(char_code_as_string);        //using this way
    printf("%c - %s\n", char_code, ecsape[char_code]);
    
    char ch = '9';                                   //char code as char
    int chc = ch-'0';                                //int from char
    printf("%c - %s\n", chc, ecsape[chc]);           //tab-symbol with code 9 + escaped
    
    
    if(!strcmp(ecsape['\2'], "\2")){printf("yeap\n\n");}
    
    //single escaped characters
    printf("%s\n", ecsape['\t']);
    printf("%s\n", ecsape['\r']);
    printf("%s\n", ecsape['\n']);
}

Show compiler warnings [ + ] Compiler args [ + ] Show input
Compilation time: 0.39 sec, absolute running time: 0.38 sec, cpu time: 0.25 sec, memory peak: 3 Mb, absolute service time: 0,78 sec