1 /* 2 * Copyright (c) 2014-2020 Pavel Kalvoda <me@pavelkalvoda.com> 3 * 4 * libcbor is free software; you can redistribute it and/or modify 5 * it under the terms of the MIT license. See LICENSE for details. 6 */ 7 8 #include <stdio.h> 9 #include "cbor.h" 10 11 void usage(void) { 12 printf("Usage: readfile [input file]\n"); 13 exit(1); 14 } 15 16 /* 17 * Reads data from a file. Example usage: 18 * $ ./examples/readfile examples/data/nested_array.cbor 19 */ 20 21 int main(int argc, char* argv[]) { 22 if (argc != 2) usage(); 23 FILE* f = fopen(argv[1], "rb"); 24 if (f == NULL) usage(); 25 fseek(f, 0, SEEK_END); 26 size_t length = (size_t)ftell(f); 27 fseek(f, 0, SEEK_SET); 28 unsigned char* buffer = malloc(length); 29 fread(buffer, length, 1, f); 30 31 /* Assuming `buffer` contains `length` bytes of input data */ 32 struct cbor_load_result result; 33 cbor_item_t* item = cbor_load(buffer, length, &result); 34 free(buffer); 35 36 if (result.error.code != CBOR_ERR_NONE) { 37 printf( 38 "There was an error while reading the input near byte %zu (read %zu " 39 "bytes in total): ", 40 result.error.position, result.read); 41 switch (result.error.code) { 42 case CBOR_ERR_MALFORMATED: { 43 printf("Malformed data\n"); 44 break; 45 } 46 case CBOR_ERR_MEMERROR: { 47 printf("Memory error -- perhaps the input is too large?\n"); 48 break; 49 } 50 case CBOR_ERR_NODATA: { 51 printf("The input is empty\n"); 52 break; 53 } 54 case CBOR_ERR_NOTENOUGHDATA: { 55 printf("Data seem to be missing -- is the input complete?\n"); 56 break; 57 } 58 case CBOR_ERR_SYNTAXERROR: { 59 printf( 60 "Syntactically malformed data -- see " 61 "https://www.rfc-editor.org/info/std94\n"); 62 break; 63 } 64 case CBOR_ERR_NONE: { 65 // GCC's cheap dataflow analysis gag 66 break; 67 } 68 } 69 exit(1); 70 } 71 72 /* Pretty-print the result */ 73 cbor_describe(item, stdout); 74 fflush(stdout); 75 /* Deallocate the result */ 76 cbor_decref(&item); 77 78 fclose(f); 79 } 80