ini_reader.c

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#include "ini_reader.h"
#include "cfg/cfg_ini_reader.h"
#include <string.h>
#include <stdio.h>
#include <ctype.h>

/*
 * Returns when the line containing the section is found.
 * The file pointer is positioned at the start of the next line.
 * Returns EOF if no section was found, 0 otherwise.
 */
static int findSection(KFile *fd, const char *section, size_t section_len, char *line, size_t size)
{
    while (kfile_gets(fd, line, size) != EOF)
    {
        char *ptr = line;
        unsigned i;
        /* accept only sections that begin at first char */
        if (*ptr++ != '[')
            continue;

        /* find the end-of-section character */
        for (i = 0; i < size && *ptr != ']'; ++i, ++ptr)
            ;

        /* The found section could be long that our section key */
        if (section_len != i)
            continue;

        /* did we find the correct section? */
        if(strncmp(&line[1], section, section_len))
            continue;
        else
            return 0;
    }
    return EOF;
}

/*
 * Fills the argument with the key found in line
 */
static char *getKey(const char *line, char *key, size_t size)
{
    /* null-terminated string */
    while (isspace((unsigned char)*line))
        ++line;
    int i = 0;
    while (*line != '=' && !isspace((unsigned char)*line) && size)
    {
        key[i++] = *line;
        ++line;
        --size;
    }
    size ? (key[i] = '\0') : (key[i-1] = '\0');
    return key;
}

/*
 * Fills the argument with the value found in line.
 */
static char *getValue(const char *line, char *value, size_t size)
{
    while (*line++ != '=')
        ;
    while (isspace((unsigned char)*line))
        ++line;
    int i = 0;
    while (*line && size)
    {
        value[i++] = *line++;
        --size;
    }
    size ? (value[i] = '\0') : (value[i-1] = '\0');
    return value;
}

static int findKey(KFile *fd, const char *key, char *line, size_t size)
{
    int err;
    do
    {
        err = kfile_gets(fd, line, size);
        char curr_key[30];
        getKey(line, curr_key, 30);
        /* check key */
        if (!strcmp(curr_key, key))
            return 0;
    }
    while (err != EOF && *line != '[');
    return EOF;
}

/*
 * On errors, the function returns EOF and fills the buffer with the default value.
 */
int ini_getString(KFile *fd, const char *section, const char *key, const char *default_value, char *buf, size_t size)
{
    char line[CONFIG_INI_MAX_LINE_LEN];

    if (kfile_seek(fd, 0, KSM_SEEK_SET) == EOF)
        goto error;

    if (findSection(fd, section, strlen(section), line, CONFIG_INI_MAX_LINE_LEN) == EOF)
        goto error;

    if (findKey(fd, key, line, CONFIG_INI_MAX_LINE_LEN) == EOF)
        goto error;
    else
        getValue(line, buf, size);
    return 0;

error:
    strncpy(buf, default_value, size);
    if (size > 0)
        buf[size - 1] = '\0';
    return EOF;
}