Add missing functions to string.h

tests/string/stpcpy.c

@@ -0,0 +1,26 @@
+#include <string.h>
+#include <assert.h>
+
+void test_stpcpy(const char *src, char *dest) {
+    char *end = stpcpy(dest, src);
+    assert(strcmp(dest, src) == 0);
+    assert(*end == '\0');
+    assert(end == dest + strlen(dest));
+}
+
+int main() {
+    char dest[20];
+
+    test_stpcpy("Hello, World!", dest);
+
+    // Test case 2: Empty string
+    test_stpcpy("", dest);
+
+    // Test case 3: String with special characters
+    test_stpcpy("Special chars: !@#$%^&*()", dest);
+
+    // Test case 4: String with spaces
+    test_stpcpy("A string with spaces", dest);
+
+    return 0;
+}

tests/string/stpncpy.c

@@ -0,0 +1,40 @@
+#include <string.h>
+#include <assert.h>
+
+int main() {
+    // Define some test strings
+    const char *src = "Hello, World!";
+    char dest[50];
+    
+    // Test 1: Copy exactly 5 characters from src to dest
+    char *result = stpncpy(dest, src, 5);
+    dest[5] = '\0';  // Ensure the destination string is null-terminated
+    assert(strcmp(dest, "Hello") == 0);  // Verify the string in dest
+    assert(result == &dest[5]);  // Ensure the return pointer points to the null terminator
+
+    // Test 2: Copy 15 characters from src to dest (more than the length of src)
+    result = stpncpy(dest, src, 15);
+    dest[13] = '\0';  // Ensure the destination string is null-terminated
+    assert(strcmp(dest, "Hello, World!") == 0);  // Verify the string in dest
+    assert(result == &dest[13]);  // Ensure the return pointer points to the null terminator
+
+    // Test 3: Copy 3 characters from src to dest
+    result = stpncpy(dest, src, 3);
+    dest[3] = '\0';  // Ensure the destination string is null-terminated
+    assert(strcmp(dest, "Hel") == 0);  // Verify the string in dest
+    assert(result == &dest[3]);  // Ensure the return pointer points to the null terminator
+
+    // Test 4: Copy 0 characters from src to dest
+    result = stpncpy(dest, src, 0);
+    dest[0] = '\0';  // Ensure the destination is explicitly null-terminated
+    assert(dest[0] == '\0');  // Ensure the destination is an empty string
+    assert(result == dest);  // Ensure the return pointer points to the start of dest
+
+    // Test 5: Copy exactly the length of the source string
+    result = stpncpy(dest, src, strlen(src));
+    dest[strlen(src)] = '\0';  // Ensure the destination string is null-terminated
+    assert(strcmp(dest, "Hello, World!") == 0);  // Verify the string in dest
+    assert(result == &dest[strlen(src)]);  // Ensure the return pointer points to the null terminator
+
+    return 0;
+}

tests/string/strchrnul.c

@@ -0,0 +1,31 @@
+#include <string.h>
+#include <assert.h>
+
+
+int main() {
+    // Test 1: Character is present in the string
+    const char *str1 = "Hello, World!";
+    const char *result1 = strchrnul(str1, 'o');
+    assert(result1 == &str1[4]); // 'o' is at position 4 in "Hello, World!"
+
+    // Test 2: Character is not in the string (should return the null terminator)
+    const char *str2 = "Hello, World!";
+    const char *result2 = strchrnul(str2, 'z');
+    assert(result2 == &str2[13]); // 'z' is not present, so it returns the null terminator
+
+    // Test 3: Character is the first character in the string
+    const char *str3 = "abcdef";
+    const char *result3 = strchrnul(str3, 'a');
+    assert(result3 == &str3[0]); // 'a' is at position 0
+
+    // Test 4: Character is the last character in the string
+    const char *str4 = "abcdef";
+    const char *result4 = strchrnul(str4, 'f');
+    assert(result4 == &str4[5]); // 'f' is at position 5, the last character
+
+    // Test 5: Searching for the null terminator itself
+    const char *str5 = "abcdef";
+    const char *result5 = strchrnul(str5, '\0');
+    assert(result5 == &str5[6]); // The null terminator is at position 6 (end of the string)
+    return 0;
+}

tests/string/strsep.c

@@ -0,0 +1,68 @@
+#include <string.h>
+#include <assert.h>
+
+int main() {
+    // Test case 1: Basic case with multiple tokens
+    char str1[] = "apple,orange,banana";
+    char *delim = ",";
+    char *token = str1;
+    char *result = NULL;
+
+    // First token should be "apple"
+    result = strsep(&token, delim);
+    assert(result != NULL && strcmp(result, "apple") == 0);
+
+    // Second token should be "orange"
+    result = strsep(&token, delim);
+    assert(result != NULL && strcmp(result, "orange") == 0);
+
+    // Third token should be "banana"
+    result = strsep(&token, delim);
+    assert(result != NULL && strcmp(result, "banana") == 0);
+
+    // No more tokens
+    result = strsep(&token, delim);
+    assert(result == NULL);
+
+    // Test case 2: Empty string
+    char str2[] = "";
+    token = str2;
+    result = strsep(&token, delim);
+
+    // Test case 3: String with no delimiter
+    char str3[] = "apple";
+    token = str3;
+    result = strsep(&token, delim);
+    assert(result != NULL && strcmp(result, "apple") == 0);
+    assert(token == NULL);  // No more tokens
+
+    // Test case 4: String starts with delimiter
+    char str4[] = ",apple,orange";
+    token = str4;
+    result = strsep(&token, delim);
+    assert(result != NULL && strlen(result) == 0);  // First token should be an empty string ("")
+
+    result = strsep(&token, delim);
+    assert(result != NULL && strcmp(result, "apple") == 0);
+
+    // Test case 5: Multiple delimiters in a row
+    char str5[] = "apple,,orange";
+    token = str5;
+    result = strsep(&token, delim);
+    assert(result != NULL && strcmp(result, "apple") == 0);
+    result = strsep(&token, delim);
+    assert(result != NULL && strlen(result) == 0);  // Empty token due to consecutive delimiters
+    result = strsep(&token, delim);
+    assert(result != NULL && strcmp(result, "orange") == 0);
+
+    // Test case 6: Delimiters at the end of the string
+    char str6[] = "apple,orange,";
+    token = str6;
+    result = strsep(&token, delim);
+    assert(result != NULL && strcmp(result, "apple") == 0);
+    result = strsep(&token, delim);
+    assert(result != NULL && strcmp(result, "orange") == 0);
+    result = strsep(&token, delim);
+
+    return 0;
+}