Basic key/value in C, including simple unit test system

dict.c

/* A key/value dict system in C */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>

#define TEST TRUE /* Do the unit tests */

typedef struct dict_t_struct {
    char *key;
    char *value;
    struct dict_t_struct *next;
} dict_t;

static dict_t *config = NULL;

int configLen() {
    int count = 0;
    dict_t *ptr;
    for (ptr = config; ptr != NULL; ptr = ptr->next)
        count++;
    return count;
}

void configAddItem(char *key, char *value) {
    dict_t *ptr;
    dict_t *new;
#ifdef DEBUG
    printf("Adding key '%s' value '%s'\n", key, value);
#endif
    for (ptr = config; ptr != NULL; ptr = ptr->next) {
        if (strcmp(ptr->key, key) == 0) {
            ptr->value = realloc(ptr->value, strlen(value)+1);
            strcpy(ptr->value, value);
            return;
        }
    }
    new = malloc(sizeof(struct dict_t_struct));
    new->key = malloc(strlen(key)+1);
    new->value = malloc(strlen(value)+1);
    strcpy(new->key, key);
    strcpy(new->value, value);
    new->next = config;
    config = new;
    return;
}

void configPrint() {
    dict_t *ptr;
    int count = 1;
    if (config == NULL) printf("config is empty\n");
    else printf("config entries:\n");
    for (ptr = config; ptr != NULL; ptr = ptr->next) {
        printf("-- Entry %d Key '%s' -> Value '%s' / Next '%s'\n", count++, ptr->key, ptr->value, ptr->next == NULL ? "NO":"YES");
    }
}

void configDel() {
    dict_t *ptr;
    while (config != NULL) {
        ptr = config;
        config = config->next;
#ifdef DEBUG
        printf("Cleanup entry key '%s' value '%s'\n", ptr->key, ptr->value);
#endif
        free(ptr->key);
        free(ptr->value);
        free(ptr);
    }
}

char *configGetItem(char *key) {
    dict_t *ptr;
    for (ptr = config; ptr != NULL; ptr = ptr->next) {
        if (strcmp(ptr->key, key) == 0) {
            return ptr->value;
        }
    }
    return NULL;
}

void configDelItem(char *key) {
    dict_t *ptr, *prev;
    ptr = config;
    prev = NULL;
    while(ptr != NULL) {
        if(strcmp(ptr->key, key) == 0) {
            if      (prev == NULL && ptr->next != NULL)
                config = ptr->next;
            else if (prev != NULL && ptr->next != NULL)
                prev->next = ptr->next;
            else if (prev == NULL && ptr->next == NULL)
                config = NULL;
            else
                prev->next = NULL;
#ifdef DEBUG
            printf("Remove key '%s' value '%s'\n", ptr->key, ptr->value);
#endif
            free(ptr->key);
            free(ptr->value);
            free(ptr);
            return;
        }
        prev = ptr;
        ptr = ptr->next;
    }
    printf("Del: Key '%s' not in config\n", key);
}

#ifdef TEST

void test_setup() {
    config = NULL;
}

void test_teardown() {
    configDel();
}

void test_empty_len() {
    assert(configLen() == 0);
}

void test_add_foo() {
    configAddItem("foo", "bar");
    assert(strcmp(configGetItem("foo"), "bar") == 0);
    assert(configGetItem("bar") == NULL);
    assert(configLen() == 1);
}

void test_add_foo_bar() {
    configAddItem("foo", "bar");
    configAddItem("bar", "foo");
    assert(strcmp(configGetItem("foo"), "bar") == 0);
    assert(strcmp(configGetItem("bar"), "foo") == 0);
    assert(configLen() == 2);
}

void test_remove_top() {
    configAddItem("foo", "bar");
    configAddItem("bar", "foo");
    configAddItem("barbar", "foo2");
    assert(configLen() == 3);
    configDelItem("barbar");
    assert(configLen() == 2);
    assert(strcmp(configGetItem("foo"), "bar") == 0);
    assert(strcmp(configGetItem("bar"), "foo") == 0);
    assert(configGetItem("barbar") == NULL);
}

void test_remove_mid() {
    configAddItem("foo", "bar");
    configAddItem("bar", "foo");
    configAddItem("barbar", "foo2");
    assert(configLen() == 3);
    configDelItem("bar");
    assert(configLen() == 2);
    assert(strcmp(configGetItem("foo"), "bar") == 0);
    assert(configGetItem("bar") == NULL);
    assert(strcmp(configGetItem("barbar"), "foo2") == 0);
}

void test_remove_last() {
    configAddItem("foo", "bar");
    configAddItem("bar", "foo");
    configAddItem("barbar", "foo2");
    assert(configLen() == 3);
    configDelItem("foo");
    assert(configLen() == 2);
    assert(configGetItem("foo") == NULL);
    assert(strcmp(configGetItem("bar"), "foo") == 0);
    assert(strcmp(configGetItem("barbar"), "foo2") == 0);
}

struct test_def {
    void (*test)();
    char *testname;
};

struct test_def tests[] = {
    {test_empty_len,   "Test empty dict length      "},
    {test_add_foo,     "Test add one entry          "},
    {test_add_foo_bar, "Test add two entries        "},
    {test_remove_top,  "Test remove from top of dict"},
    {test_remove_mid,  "Test remove from mid of dict"},
    {test_remove_last, "Test remove last entry      "},
    {NULL,           ""}
};

int main(int argc, char **argv) {
    int test_count = 0;
    while(tests[test_count].test != NULL) {
        test_setup();
        printf("Do test '%s' - ", tests[test_count].testname);
        tests[test_count].test();
        printf("[OK]\n");
        test_teardown();
        test_count++;
    }
}

#endif