Tizen Native API
4.0
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Hash table in action
//Compile with: //gcc -g eina_hash_01.c -o eina_hash_01 `pkg-config --cflags --libs eina` #include <stdio.h> #include <string.h> #include <Eina.h> /* * Eina Hash - phonebook * * This example demonstrate the use of Eina Hash by implementing a phonebook * that stores its contact data into the hash. * * It indexes the phone numbers by Contact Full Name, so it's a hash with * string keys. */ struct _Phone_Entry { const char *name; // Full name. const char *number; // Phone number. }; typedef struct _Phone_Entry Phone_Entry; static Phone_Entry _start_entries[] = { { "Wolfgang Amadeus Mozart", "+01 23 456-78910" }, { "Ludwig van Beethoven", "+12 34 567-89101" }, { "Richard Georg Strauss", "+23 45 678-91012" }, { "Heitor Villa-Lobos", "+34 56 789-10123" }, { NULL, NULL } }; // _start_entries static void _phone_entry_free_cb(void *data) { free(data); } static Eina_Bool _phone_book_foreach_cb(const Eina_Hash *phone_book EINA_UNUSED, const void *key, void *data, void *fdata EINA_UNUSED) { const char *name = key; const char *number = data; printf("%s: %s\n", name, number); // Return EINA_FALSE to stop this callback from being called return EINA_TRUE; } int main(int argc, const char *argv[]) { (void) argc; (void) argv; Eina_Hash *phone_book = NULL; int i; const char *entry_name = "Heitor Villa-Lobos"; char *phone = NULL; Eina_Bool r; Eina_Iterator *it; void *data; eina_init(); phone_book = eina_hash_string_superfast_new(_phone_entry_free_cb); // Add initial entries to our hash for (i = 0; _start_entries[i].name != NULL; i++) { eina_hash_add(phone_book, _start_entries[i].name, strdup(_start_entries[i].number)); } // Look for a specific entry and get its phone number phone = eina_hash_find(phone_book, entry_name); if (phone) { printf("Printing entry.\n"); printf("Name: %s\n", entry_name); printf("Number: %s\n\n", phone); } // Delete this entry r = eina_hash_del(phone_book, entry_name, NULL); printf("Hash entry successfully deleted? %d\n\n", r); // Modify the pointer data of an entry and free the old one phone = eina_hash_modify(phone_book, "Richard Georg Strauss", strdup("+23 45 111-11111")); free(phone); // Modify or add an entry to the hash with eina_hash_set // Let's first add a new entry phone = eina_hash_set(phone_book, "Raul Seixas", strdup("+55 01 234-56789")); if (!phone) { printf("No previous phone found for Raul Seixas. "); printf("Creating new entry.\n"); } else { printf("Old phone for Raul Seixas was %s\n", phone); free(phone); } printf("\n"); // Now change the phone number phone = eina_hash_set(phone_book, "Raul Seixas", strdup("+55 02 222-22222")); if (phone) { printf("Changing phone for Raul Seixas to +55 02 222-22222. "); printf("Old phone was %s\n", phone); free(phone); } else { printf("No previous phone found for Raul Seixas. "); printf("Creating new entry.\n"); } // There are many ways to iterate over our Phone book. // First, iterate showing the names and associated numbers. printf("List of phones:\n"); eina_hash_foreach(phone_book, _phone_book_foreach_cb, NULL); printf("\n"); // Now iterate using an iterator printf("List of phones:\n"); it = eina_hash_iterator_tuple_new(phone_book); while (eina_iterator_next(it, &data)) { Eina_Hash_Tuple *t = data; const char *name = t->key; const char *number = t->data; printf("%s: %s\n", name, number); } eina_iterator_free(it); // Always free the iterator after its use printf("\n"); // Just iterate over the keys (names) printf("List of names in the phone book:\n"); it = eina_hash_iterator_key_new(phone_book); while (eina_iterator_next(it, &data)) { const char *name = data; printf("%s\n", name); } eina_iterator_free(it); printf("\n"); // Just iterate over the data (numbers) printf("List of numbers in the phone book:\n"); it = eina_hash_iterator_data_new(phone_book); while (eina_iterator_next(it, &data)) { const char *number = data; printf("%s\n", number); } eina_iterator_free(it); printf("\n"); // Check how many items are in the phone book printf("There are %d items in the hash.\n\n", eina_hash_population(phone_book)); // Change the name (key) on an entry eina_hash_move(phone_book, "Raul Seixas", "Alceu Valenca"); printf("List of phones after change:\n"); eina_hash_foreach(phone_book, _phone_book_foreach_cb, NULL); printf("\n"); // Empty the phone book, but don't destroy it eina_hash_free_buckets(phone_book); printf("There are %d items in the hash.\n\n", eina_hash_population(phone_book)); // Phone book could still be used, but we are freeing it since we are // done for now eina_hash_free(phone_book); eina_shutdown(); }