/* inih -- simple .INI file parser

SPDX-License-Identifier: BSD-3-Clause

Copyright (C) 2009-2025, Ben Hoyt

inih is released under the New BSD license (see LICENSE.txt). Go to the project

home page for more info:

https://github.com/benhoyt/inih

*/

#if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS)

#define _CRT_SECURE_NO_WARNINGS

#endif

#include <stdio.h>

#include <ctype.h>

#include <string.h>

#include <assert.h>

#include "ini.h"

#if !INI_USE_STACK

#if INI_CUSTOM_ALLOCATOR

#include <stddef.h>

void* ini_malloc(size_t size);

void ini_free(void* ptr);

void* ini_realloc(void* ptr, size_t size);

#else

#include <stdlib.h>

#define ini_malloc malloc

#define ini_free free

#define ini_realloc realloc

#endif

#endif

/* Used by ini_parse_string() to keep track of string parsing state. */

typedef struct {

    const char* ptr;

    size_t num_left;

} ini_parse_string_ctx;

/* Strip whitespace chars off end of given string, in place. end must be a

   pointer to the NUL terminator at the end of the string. Return s. */

static char* ini_rstrip(char* s, char* end)

{

    while (end > s && isspace((unsigned char)(*--end)))

        *end = '\0';

    return s;

}

/* Return pointer to first non-whitespace char in given string. */

static char* ini_lskip(const char* s)

{

    while (*s && isspace((unsigned char)(*s)))

        s++;

    return (char*)s;

}

/* Return pointer to first char (of chars) or inline comment in given string,

   or pointer to NUL at end of string if neither found. Inline comment must

   be prefixed by a whitespace character to register as a comment. */

static char* ini_find_chars_or_comment(const char* s, const char* chars)

{

#if INI_ALLOW_INLINE_COMMENTS

    int was_space = 0;

    while (*s && (!chars || !strchr(chars, *s)) &&

           !(was_space && strchr(INI_INLINE_COMMENT_PREFIXES, *s))) {

        was_space = isspace((unsigned char)(*s));

        s++;

    }

#else

    while (*s && (!chars || !strchr(chars, *s))) {

        s++;

    }

#endif

    return (char*)s;

}

/* Similar to strncpy, but ensures dest (size bytes) is

   NUL-terminated, and doesn't pad with NULs. */

static char* ini_strncpy0(char* dest, const char* src, size_t size)

{

    /* Could use strncpy internally, but it causes gcc warnings (see issue #91) */

    size_t i;

    for (i = 0; i < size - 1 && src[i]; i++)

        dest[i] = src[i];

    dest[i] = '\0';

    return dest;

}

/* See documentation in header file. */

int ini_parse_stream(ini_reader reader, void* stream, ini_handler handler,

                     void* user)

{

    /* Uses a fair bit of stack (use heap instead if you need to) */

#if INI_USE_STACK

    char line[INI_MAX_LINE];

    size_t max_line = INI_MAX_LINE;

#else

    char* line;

    size_t max_line = INI_INITIAL_ALLOC;

#endif

#if INI_ALLOW_REALLOC && !INI_USE_STACK

    char* new_line;

#endif

    char section[INI_MAX_SECTION] = "";

#if INI_ALLOW_MULTILINE

    char prev_name[INI_MAX_NAME] = "";

#endif

    size_t offset;

    char* start;

    char* end;

    char* name;

    char* value;

    int lineno = 0;

    int error = 0;

    char abyss[16];  /* Used to consume input when a line is too long. */

    size_t abyss_len;

    assert(reader != NULL);

    assert(stream != NULL);

    assert(handler != NULL);

#if !INI_USE_STACK

    line = (char*)ini_malloc(INI_INITIAL_ALLOC);

    if (!line) {

        return -2;

    }

#endif

#if INI_HANDLER_LINENO

#define HANDLER(u, s, n, v) handler(u, s, n, v, lineno)

#else

#define HANDLER(u, s, n, v) handler(u, s, n, v)

#endif

    /* Scan through stream line by line */

    while (reader(line, (int)max_line, stream) != NULL) {

        offset = strlen(line);

#if INI_ALLOW_REALLOC && !INI_USE_STACK

        while (max_line < INI_MAX_LINE &&

               offset == max_line - 1 && line[offset - 1] != '\n') {

            max_line *= 2;

            if (max_line > INI_MAX_LINE)

                max_line = INI_MAX_LINE;

            new_line = ini_realloc(line, max_line);

            if (!new_line) {

                ini_free(line);

                return -2;

            }

            line = new_line;

            if (reader(line + offset, (int)(max_line - offset), stream) == NULL)

                break;

            offset += strlen(line + offset);

        }

#endif

        lineno++;

        /* If line exceeded INI_MAX_LINE bytes, discard till end of line. */

        if (offset == max_line - 1 && line[offset - 1] != '\n') {

            while (reader(abyss, sizeof(abyss), stream) != NULL) {

                if (!error)

                    error = lineno;

                abyss_len = strlen(abyss);

                if (abyss_len > 0 && abyss[abyss_len - 1] == '\n')

                    break;

            }

        }

        start = line;

#if INI_ALLOW_BOM

        if (lineno == 1 && (unsigned char)start[0] == 0xEF &&

                           (unsigned char)start[1] == 0xBB &&

                           (unsigned char)start[2] == 0xBF) {

            start += 3;

        }

#endif

        start = ini_rstrip(ini_lskip(start), line + offset);

        if (strchr(INI_START_COMMENT_PREFIXES, *start)) {

            /* Start-of-line comment */

        }

#if INI_ALLOW_MULTILINE

        else if (*prev_name && *start && start > line) {

#if INI_ALLOW_INLINE_COMMENTS

            end = ini_find_chars_or_comment(start, NULL);

            *end = '\0';

            ini_rstrip(start, end);

#endif

            /* Non-blank line with leading whitespace, treat as continuation

               of previous name's value (as per Python configparser). */

            if (!HANDLER(user, section, prev_name, start) && !error)

                error = lineno;

        }

#endif

        else if (*start == '[') {

            /* A "[section]" line */

            end = ini_find_chars_or_comment(start + 1, "]");

            if (*end == ']') {

                *end = '\0';

                ini_strncpy0(section, start + 1, sizeof(section));

#if INI_ALLOW_MULTILINE

                *prev_name = '\0';

#endif

#if INI_CALL_HANDLER_ON_NEW_SECTION

                if (!HANDLER(user, section, NULL, NULL) && !error)

                    error = lineno;

#endif

            }

            else if (!error) {

                /* No ']' found on section line */

                error = lineno;

            }

        }

        else if (*start) {

            /* Not a comment, must be a name[=:]value pair */

            end = ini_find_chars_or_comment(start, "=:");

            if (*end == '=' || *end == ':') {

                *end = '\0';

                name = ini_rstrip(start, end);

                value = end + 1;

#if INI_ALLOW_INLINE_COMMENTS

                end = ini_find_chars_or_comment(value, NULL);

                *end = '\0';

#endif

                value = ini_lskip(value);

                ini_rstrip(value, end);

#if INI_ALLOW_MULTILINE

                ini_strncpy0(prev_name, name, sizeof(prev_name));

#endif

                /* Valid name[=:]value pair found, call handler */

                if (!HANDLER(user, section, name, value) && !error)

                    error = lineno;

            }

            else {

                /* No '=' or ':' found on name[=:]value line */

#if INI_ALLOW_NO_VALUE

                *end = '\0';

                name = ini_rstrip(start, end);

                if (!HANDLER(user, section, name, NULL) && !error)

                    error = lineno;

#else

                if (!error)

                    error = lineno;

#endif

            }

        }

#if INI_STOP_ON_FIRST_ERROR

        if (error)

            break;

#endif

    }

#if !INI_USE_STACK

    ini_free(line);

#endif

    return error;

}

/* See documentation in header file. */

int ini_parse_file(FILE* file, ini_handler handler, void* user)

{

    return ini_parse_stream((ini_reader)fgets, file, handler, user);

}

/* See documentation in header file. */

int ini_parse(const char* filename, ini_handler handler, void* user)

{

    FILE* file;

    int error;

    file = fopen(filename, "r");

    if (!file)

        return -1;

    error = ini_parse_file(file, handler, user);

    fclose(file);

    return error;

}

/* An ini_reader function to read the next line from a string buffer. This

   is the fgets() equivalent used by ini_parse_string(). */

static char* ini_reader_string(char* str, int num, void* stream) {

    ini_parse_string_ctx* ctx = (ini_parse_string_ctx*)stream;

    const char* ctx_ptr = ctx->ptr;

    size_t ctx_num_left = ctx->num_left;

    char* strp = str;

    char c;

    if (ctx_num_left == 0 || num < 2)

        return NULL;

    while (num > 1 && ctx_num_left != 0) {

        c = *ctx_ptr++;

        ctx_num_left--;

        *strp++ = c;

        if (c == '\n')

            break;

        num--;

    }

    *strp = '\0';

    ctx->ptr = ctx_ptr;

    ctx->num_left = ctx_num_left;

    return str;

}

/* See documentation in header file. */

int ini_parse_string(const char* string, ini_handler handler, void* user) {

    return ini_parse_string_length(string, strlen(string), handler, user);

}

/* See documentation in header file. */

int ini_parse_string_length(const char* string, size_t length,

                            ini_handler handler, void* user) {

    ini_parse_string_ctx ctx;

    ctx.ptr = string;

    ctx.num_left = length;

    return ini_parse_stream((ini_reader)ini_reader_string, &ctx, handler,

                            user);

}