1 /* 2 * This file is licensed under the GPL license. For the full content 3 * of this license, see the COPYING file at the top level of this 4 * source tree. 5 */ 6 7 /* 8 * assertion: 9 * 10 * The function will copy not more than n bytes (bytes that follow a NUL 11 * character are not copied) from the array pointed to by s1 to the array 12 * pointed to by s2. And it will return s2. 13 14 * method: 15 * -Generate sample string s1 of variable lengths in a loop. 16 * -Use strncpy() to copy s1 into sample string s2 in each iteration 17 * with given n value. 18 * -Truncate last n characters of s1 and 19 * -Compare both strings(s1 and s2) and Also compare returned pointer with s2. 20 * -Repeat the above steps for given number of iterations. 21 */ 22 23 #include <stdio.h> 24 #include <string.h> 25 #include <stdlib.h> 26 #include <unistd.h> 27 #include "posixtest.h" 28 29 #define STRING_MAX_LEN 50000 30 #define STEP_COUNT 2000 31 #define TNAME "strncpy/1-1.c" 32 33 char *random_string(int len) 34 { 35 int i; 36 char *output_string = NULL; 37 output_string = malloc(len + 1); 38 if (output_string == NULL) { 39 printf(TNAME " Failed to allocate memory\n"); 40 exit(PTS_UNRESOLVED); 41 } 42 for (i = 0; i < len; i++) 43 /* Limiting characters from 1-255 */ 44 output_string[i] = rand() % 254 + 1; 45 output_string[len] = '\0'; 46 return output_string; 47 } 48 49 int main(void) 50 { 51 char *ret_str; 52 int i, num_bytes; 53 54 for (i = 1; i < STRING_MAX_LEN; i += STEP_COUNT) { 55 char *sample_str_1; 56 char *sample_str_2 = malloc(i - 1); 57 if (sample_str_2 == NULL) { 58 printf(TNAME " Failed to allocate memory\n"); 59 exit(PTS_UNRESOLVED); 60 } 61 sample_str_1 = random_string(i); 62 num_bytes = rand() % i; 63 64 ret_str = strncpy(sample_str_2, sample_str_1, num_bytes); 65 66 sample_str_2[num_bytes] = '\0'; 67 sample_str_1[num_bytes] = '\0'; 68 69 if (strcmp(sample_str_2, sample_str_1) != 0 70 && ret_str == sample_str_2) { 71 printf(TNAME " Test Failed, string copy failed. " 72 "Expected string: %s\n, But got: %s\n" 73 , sample_str_1, sample_str_2); 74 exit(PTS_FAIL); 75 } else if (ret_str != sample_str_2) { 76 printf(TNAME " Test Failed, return is not as expected. " 77 "Expected: %p, But obtained: %p\n" 78 , sample_str_2, ret_str); 79 exit(PTS_FAIL); 80 } 81 free(sample_str_1); 82 free(sample_str_2); 83 } 84 printf(TNAME " Test Passed, string copied successfully\n"); 85 exit(PTS_PASS); 86 } 87
