src/examples/eina_model_03.c

   1 //Compile with:
   2 //gcc -g eina_model_03.c -o eina_model_03 `pkg-config --cflags --libs eina`
   3
   4 #include <Eina.h>
   5 #include <string.h>
   6 #include <stdio.h>
   7 #include <errno.h>
   8
   9 static Eina_Model_Type *ADDRESS_BOOK_TYPE;
  10 static Eina_Model_Type *PERSON_TYPE;
  11
  12 static void address_book_init(void);
  13
  14 int main(void)
  15 {
  16    Eina_Model *address_book;
  17    Eina_Value val;
  18    int i, count;
  19    char *s;
  20
  21    eina_init();
  22
  23    address_book_init();
  24
  25    address_book = eina_model_new(ADDRESS_BOOK_TYPE);
  26
  27    eina_value_setup(&val, EINA_VALUE_TYPE_STRING);
  28    eina_value_set(&val, "addr_book.txt");
  29    eina_model_property_set(address_book, "filename", &val);
  30    eina_value_flush(&val);
  31
  32    eina_model_load(address_book);
  33    s = eina_model_to_string(address_book);
  34    printf("model as string:\n%s\n\n", s);
  35    free(s);
  36
  37    count = eina_model_child_count(address_book);
  38    printf("Address Book with %d entries:\n", count);
  39    for (i = 0; i < count; i++)
  40      {
  41         Eina_Model *person = eina_model_child_get(address_book, i);
  42         Eina_Value nameval, emailval;
  43         const char *name, *email;
  44
  45         eina_model_property_get(person, "name", &nameval);
  46         eina_model_property_get(person, "email", &emailval);
  47
  48         eina_value_get(&nameval, &name);
  49         eina_value_get(&emailval, &email);
  50
  51         printf("%02d \"%s\" <%s>\n", i, name, email);
  52
  53         // We don't need property values anymore
  54         eina_value_flush(&nameval);
  55         eina_value_flush(&emailval);
  56
  57         // We don't need our reference to person anymore
  58         eina_model_unref(person);
  59      }
  60
  61    eina_model_unref(address_book);
  62    eina_shutdown();
  63
  64    return 0;
  65 }
  66
  67 // Structure Descriptions are just used internally in the type constructors:
  68 static Eina_Value_Struct_Desc *ADDRESS_BOOK_DESC;
  69 static Eina_Value_Struct_Desc *PERSON_DESC;
  70
  71 static Eina_Bool
  72 _person_constructor(Eina_Model *model)
  73 {
  74    // call parent type constructor, like "super" in other languages:
  75    if (!eina_model_type_constructor(EINA_MODEL_TYPE_STRUCT, model))
  76      return EINA_FALSE;
  77
  78    // Do specific setup of our internal structure, letting it know about
  79    // our description
  80    return eina_model_struct_set(model, PERSON_DESC, NULL);
  81 }
  82
  83 static Eina_Bool
  84 _address_book_constructor(Eina_Model *model)
  85 {
  86    // call parent type constructor, like "super" in other languages:
  87    if (!eina_model_type_constructor(EINA_MODEL_TYPE_STRUCT, model))
  88      return EINA_FALSE;
  89
  90    // Do specific setup of our internal structure, letting it know about
  91    // our description
  92    return eina_model_struct_set(model, ADDRESS_BOOK_DESC, NULL);
  93 }
  94
  95 static Eina_Bool
  96 _address_book_load(Eina_Model *model)
  97 {
  98    const char *filename;
  99    Eina_Value val;
 100    char buf[256];
 101    FILE *f;
 102
 103    // We retrieve filename from property of same name:
 104    eina_model_property_get(model, "filename", &val);
 105    eina_value_get(&val, &filename);
 106
 107    EINA_SAFETY_ON_NULL_RETURN_VAL(filename, EINA_FALSE);
 108
 109    f = fopen(filename, "r");
 110
 111    // Now that we have used filename, we must free its memory holder:
 112    eina_value_flush(&val);
 113
 114    EINA_SAFETY_ON_NULL_RETURN_VAL(f, EINA_FALSE);
 115
 116    while (fgets(buf, sizeof(buf), f))
 117      {
 118         Eina_Model *person;
 119         char *name, *email;
 120
 121         if (strlen(buf) <= 1)
 122           continue;
 123
 124         name = strtok(buf, "\t");
 125         email = strtok(NULL, "\n");
 126
 127         if ((!name) || (!email)) continue;
 128
 129         // Create person
 130         person = eina_model_new(PERSON_TYPE);
 131
 132         // Setup value type as string, as our properties are strings:
 133         eina_value_setup(&val, EINA_VALUE_TYPE_STRING);
 134
 135         // Set string properties:
 136         eina_value_set(&val, name);
 137         eina_model_property_set(person, "name", &val);
 138
 139         eina_value_set(&val, email);
 140         eina_model_property_set(person, "email", &val);
 141
 142         // Flush value, free string
 143         eina_value_flush(&val);
 144
 145         // Add person to the end of model children
 146         eina_model_child_append(model, person);
 147
 148         // Model already holds its reference to person, we release ours
 149         eina_model_unref(person);
 150      }
 151
 152    fclose(f);
 153    return EINA_TRUE;
 154 }
 155
 156 static void
 157 address_book_init(void)
 158 {
 159    // Declare type for internal struct, this is just used to easily
 160    // create Eina_Value_Struct_Member array for Eina_Value_Struct_Desc.
 161    //
 162    // We don't need this structure outside address_book_init()
 163    // as it is managed automatically by Eina_Value_Struct, used by
 164    // Eina_Model_Struct! Handy! :-)
 165    typedef struct _Person Person;
 166    struct _Person
 167    {
 168       const char *name;
 169       const char *email;
 170    };
 171    static Eina_Value_Struct_Member person_members[] = {
 172      // no eina_value_type as they are not constant initializers, see below.
 173      EINA_VALUE_STRUCT_MEMBER(NULL, Person, name),
 174      EINA_VALUE_STRUCT_MEMBER(NULL, Person, email)
 175    };
 176    // Values that cannot be set on static declarations since they are not
 177    // constant initializers. It is a nitpick from C that we need to deal with
 178    // here and on all our other declarations.
 179    person_members[0].type = EINA_VALUE_TYPE_STRING;
 180    person_members[1].type = EINA_VALUE_TYPE_STRING;
 181
 182    static Eina_Value_Struct_Desc person_desc = {
 183      EINA_VALUE_STRUCT_DESC_VERSION,
 184      NULL, // no special operations
 185      person_members,
 186      EINA_C_ARRAY_LENGTH(person_members),
 187      sizeof(Person)
 188    };
 189    static Eina_Model_Type person_type = EINA_MODEL_TYPE_INIT_NOPRIVATE
 190      ("Person_Type",
 191       Eina_Model_Type,
 192       NULL, // no type as EINA_MODEL_TYPE_STRUCT is not constant initializer!
 193       NULL, // no extra interfaces
 194       NULL  // no extra events);
 195       );
 196    person_type.parent = EINA_MODEL_TYPE_STRUCT;
 197    // Set our overloaded methods:
 198    person_type.constructor = _person_constructor;
 199
 200    typedef struct _Address_Book Address_Book;
 201    struct _Address_Book
 202    {
 203       const char *filename;
 204    };
 205    static Eina_Value_Struct_Member address_book_members[] = {
 206      // no eina_value_type as they are not constant initializers, see below.
 207      EINA_VALUE_STRUCT_MEMBER(NULL, Address_Book, filename)
 208    };
 209    address_book_members[0].type = EINA_VALUE_TYPE_STRING;
 210    static Eina_Value_Struct_Desc address_book_desc = {
 211      EINA_VALUE_STRUCT_DESC_VERSION,
 212      NULL, // no special operations
 213      address_book_members,
 214      EINA_C_ARRAY_LENGTH(address_book_members),
 215      sizeof(Address_Book)
 216    };
 217    static Eina_Model_Type address_book_type = EINA_MODEL_TYPE_INIT_NOPRIVATE
 218      ("Address_Book_Type",
 219       Eina_Model_Type,
 220       NULL, // no type as EINA_MODEL_TYPE_STRUCT is not constant initializer!
 221       NULL, // no extra interfaces
 222       NULL  // no extra events);
 223       );
 224    address_book_type.parent = EINA_MODEL_TYPE_STRUCT;
 225    // Set our overloaded methods:
 226    address_book_type.constructor = _address_book_constructor;
 227    address_book_type.load = _address_book_load;
 228
 229    // Expose the configured pointers to public usage:
 230    // NOTE: they are static, so they live after this function returns!
 231    PERSON_TYPE = &person_type;
 232    PERSON_DESC = &person_desc;
 233
 234    ADDRESS_BOOK_TYPE = &address_book_type;
 235    ADDRESS_BOOK_DESC = &address_book_desc;
 236 }