Data structure for storing multiple language versions of my software

Hello, I have created a simple program for a microcontroller. I have created a menu displayed on an LCD.
Now I want to add the possibility of choosing a language version, so that a group of strings that are used for language A are exchanged with group of strings from language B.


How to do that?


Thank you in advance for any suggestions!

I am not sure if it is applicable to you, but one of the tools used for this purpose is gettext.

Quote:

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Originally Posted by laserlight

I am not sure if it is applicable to you, but one of the tools used for this purpose is gettext.

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Thank you for your help, but it is not applicable for my idea. I am running the app on a microcontroller.

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I have an idea - is array of string arrays applicable and would solve the problem?

I would personally use something like the following:

Code:

---

#define LANGS 2

static const char *const message[][LANGS] = {

#define MSG_HELLO 0
    /* 0 */ { "Hello", "Terve" },

#define MSG_READY 1
    /* 1 */ { "Ready", "Valmis" },

#define MSG_ERROR 2
    /* 2 */ { "Error", "Virhe" },

};

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Note, however, that these strings are stored in ROM (FLASH or EEPROM), not in RAM. Some microcontrollers differentiate the two.

Quote:

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Originally Posted by Nominal Animal

I would personally use something like the following:

Code:

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#define LANGS 2
/*didnt want to copy your whole code*/

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Note, however, that these strings are stored in ROM (FLASH or EEPROM), not in RAM. Some microcontrollers differentiate the two.

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Thank you for the suggestion. However, it does not seem to work on my PC.
My code:

Code:

---

#include <stdio.h>
#include <stdlib.h>


int main()
{
    #define LANGUAGES 2


static const char *const message[][LANGUAGES] = {


#define MSG_INTRO 0
    /*0*/  { "Hello", "Witamy" },


#define MSG_MENU1 1
    /*1*/  { "Option1", "Opcja1" },


#define MSG_MENU2 2
    /*2*/  { "Option2", "Opcja2" },


};
    printf("The text is %s", message[MSG_INTRO][LANGUAGES]);
    return 0;
}

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When run - printf shows "The text is Option1".
And when I put MSG_MENU1 into printf then I get "The text is Option2".
And what is even more funny with MSG_MENU2 I get some random rubbish printed out.
Why is that happening? I am so confused.

Quote:

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Originally Posted by Pole

Thank you for the suggestion. However, it does not seem to work on my PC.

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No, because your code is wrong. The message array should be global, and here,

Quote:

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Originally Posted by Pole

Code:

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    printf("The text is %s", message[MSG_INTRO][LANGUAGES]);

---

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your latter index (LANGUAGES) is out of bounds. Remember, in C indexes start at 0, and reach up to and including SIZE-1.

Here is a fixed example:

Code:

---

#include <stdlib.h>
#include <stdio.h>

#define LANG_EN    0
#define LANG_PL    1
#define LANG_COUNT  2

static const char *const message[][LANG_COUNT] = {

#define MSG_INTRO 0
    /* 0 */ { "Hello", "Witamy" },
 
 
#define MSG_MENU1 1
    /* 1 */ { "Option1", "Opcja1" },
 

#define MSG_MENU2 2
    /* 2 */ { "Option2", "Opcja2" },

#define MSG_COUNT 3
};

int main(void)
{
    printf("message[MSG_INTRO][LANG_EN] = \"%s\"\n", message[MSG_INTRO][LANG_EN]);
    printf("message[MSG_MENU2][LANG_PL] = \"%s\"\n", message[MSG_MENU2][LANG_PL]);
    return EXIT_SUCCESS;
}

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To iterate over all possible messages in each language, use e.g.

Code:

---

int main(void)
{
    int msg, lang;

    for (msg = 0; msg < MSG_COUNT; msg++)
        for (lang = 0; lang < LANG_COUNT; lang++)
            printf("message[%d][%d] = \"%s\"\n", msg, lang, message[msg][lang]);

    return EXIT_SUCCESS;
}

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instead.