libstratosphere: add ini parsing, LZ4 compression.

Makefile

@@ -16,7 +16,7 @@ include $(DEVKITPRO)/libnx/switch_rules
 # INCLUDES is a list of directories containing header files
 #---------------------------------------------------------------------------------
 TARGET		:=	$(notdir $(CURDIR))
-SOURCES		:=	source source/spl source/spl/smc source/updater source/patcher source/map source/rnd
+SOURCES		:=	source source/spl source/spl/smc source/updater source/patcher source/map source/rnd source/util
 DATA		:=	data
 INCLUDES	:=  include
 

include/stratosphere.hpp

@@ -45,4 +45,5 @@
 
 #include "stratosphere/on_crash.hpp"
 
-#include "stratosphere/rnd.hpp"
+#include "stratosphere/rnd.hpp"
+#include "stratosphere/util.hpp"

include/stratosphere/rnd/rnd_api.hpp

@@ -15,6 +15,7 @@
  */
 
 #pragma once
+#include <limits>
 #include <switch.h>
 
 namespace sts::rnd {

include/stratosphere/util.hpp

@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2018-2019 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+#include <switch.h>
+
+#include "util/util_compression.hpp"
+#include "util/util_ini.hpp"

include/stratosphere/util/util_compression.hpp

@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2018-2019 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+#include <switch.h>
+
+namespace sts::util {
+
+    /* Compression utilities. */
+    int CompressLZ4(void *dst, size_t dst_size, const void *src, size_t src_size);
+
+    /* Decompression utilities. */
+    int DecompressLZ4(void *dst, size_t dst_size, const void *src, size_t src_size);
+
+}

include/stratosphere/util/util_ini.hpp

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2018-2019 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+#include <cstdio>
+#include <switch.h>
+
+namespace sts::util::ini {
+
+    /* Ini handler type. */
+    using Handler = int (*)(void *user_ctx, const char *section, const char *name, const char *value);
+
+    /* Utilities for dealing with INI file configuration. */
+    int ParseString(const char *ini_str, void *user_ctx, Handler h);
+    int ParseFile(FILE *f, void *user_ctx, Handler h);
+    int ParseFile(FsFile *f, void *user_ctx, Handler h);
+    int ParseFile(const char *path, void *user_ctx, Handler h);
+
+}

source/util/ini.c

@@ -0,0 +1,269 @@
+/* inih -- simple .INI file parser
+
+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 "ini.h"
+
+#if !INI_USE_STACK
+#include <stdlib.h>
+#endif
+
+#define MAX_SECTION 72
+#define MAX_NAME 72
+
+/* 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. Return s. */
+static char* rstrip(char* s)
+{
+    char* p = s + strlen(s);
+    while (p > s && isspace((unsigned char)(*--p)))
+        *p = '\0';
+    return s;
+}
+
+/* Return pointer to first non-whitespace char in given string. */
+static char* 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 null at end of string if neither found. Inline comment must
+   be prefixed by a whitespace character to register as a comment. */
+static char* 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;
+}
+
+/* Version of strncpy that ensures dest (size bytes) is null-terminated. */
+static char* strncpy0(char* dest, const char* src, size_t size)
+{
+    strncpy(dest, src, size - 1);
+    dest[size - 1] = '\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];
+    int max_line = INI_MAX_LINE;
+#else
+    char* line;
+    int max_line = INI_INITIAL_ALLOC;
+#endif
+#if INI_ALLOW_REALLOC
+    char* new_line;
+    int offset;
+#endif
+    char section[MAX_SECTION] = "";
+    char prev_name[MAX_NAME] = "";
+
+    char* start;
+    char* end;
+    char* name;
+    char* value;
+    int lineno = 0;
+    int error = 0;
+
+#if !INI_USE_STACK
+    line = (char*)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, max_line, stream) != NULL) {
+#if INI_ALLOW_REALLOC
+        offset = strlen(line);
+        while (offset == max_line - 1 && line[offset - 1] != '\n') {
+            max_line *= 2;
+            if (max_line > INI_MAX_LINE)
+                max_line = INI_MAX_LINE;
+            new_line = realloc(line, max_line);
+            if (!new_line) {
+                free(line);
+                return -2;
+            }
+            line = new_line;
+            if (reader(line + offset, max_line - offset, stream) == NULL)
+                break;
+            if (max_line >= INI_MAX_LINE)
+                break;
+            offset += strlen(line + offset);
+        }
+#endif
+
+        lineno++;
+
+        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 = lskip(rstrip(start));
+
+        if (strchr(INI_START_COMMENT_PREFIXES, *start)) {
+            /* Start-of-line comment */
+        }
+#if INI_ALLOW_MULTILINE
+        else if (*prev_name && *start && start > line) {
+            /* 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 = find_chars_or_comment(start + 1, "]");
+            if (*end == ']') {
+                *end = '\0';
+                strncpy0(section, start + 1, sizeof(section));
+                *prev_name = '\0';
+            }
+            else if (!error) {
+                /* No ']' found on section line */
+                error = lineno;
+            }
+        }
+        else if (*start) {
+            /* Not a comment, must be a name[=:]value pair */
+            end = find_chars_or_comment(start, "=:");
+            if (*end == '=' || *end == ':') {
+                *end = '\0';
+                name = rstrip(start);
+                value = end + 1;
+#if INI_ALLOW_INLINE_COMMENTS
+                end = find_chars_or_comment(value, NULL);
+                if (*end)
+                    *end = '\0';
+#endif
+                value = lskip(value);
+                rstrip(value);
+
+                /* Valid name[=:]value pair found, call handler */
+                strncpy0(prev_name, name, sizeof(prev_name));
+                if (!HANDLER(user, section, name, value) && !error)
+                    error = lineno;
+            }
+            else if (!error) {
+                /* No '=' or ':' found on name[=:]value line */
+                error = lineno;
+            }
+        }
+
+#if INI_STOP_ON_FIRST_ERROR
+        if (error)
+            break;
+#endif
+    }
+
+#if !INI_USE_STACK
+    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) {
+    ini_parse_string_ctx ctx;
+
+    ctx.ptr = string;
+    ctx.num_left = strlen(string);
+    return ini_parse_stream((ini_reader)ini_reader_string, &ctx, handler,
+                            user);
+}

source/util/ini.h

@@ -0,0 +1,130 @@
+/* inih -- simple .INI file parser
+
+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
+
+*/
+
+#ifndef __INI_H__
+#define __INI_H__
+
+/* Make this header file easier to include in C++ code */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdio.h>
+
+/* Nonzero if ini_handler callback should accept lineno parameter. */
+#ifndef INI_HANDLER_LINENO
+#define INI_HANDLER_LINENO 0
+#endif
+
+/* Typedef for prototype of handler function. */
+#if INI_HANDLER_LINENO
+typedef int (*ini_handler)(void* user, const char* section,
+                           const char* name, const char* value,
+                           int lineno);
+#else
+typedef int (*ini_handler)(void* user, const char* section,
+                           const char* name, const char* value);
+#endif
+
+/* Typedef for prototype of fgets-style reader function. */
+typedef char* (*ini_reader)(char* str, int num, void* stream);
+
+/* Parse given INI-style file. May have [section]s, name=value pairs
+   (whitespace stripped), and comments starting with ';' (semicolon). Section
+   is "" if name=value pair parsed before any section heading. name:value
+   pairs are also supported as a concession to Python's configparser.
+
+   For each name=value pair parsed, call handler function with given user
+   pointer as well as section, name, and value (data only valid for duration
+   of handler call). Handler should return nonzero on success, zero on error.
+
+   Returns 0 on success, line number of first error on parse error (doesn't
+   stop on first error), -1 on file open error, or -2 on memory allocation
+   error (only when INI_USE_STACK is zero).
+*/
+int ini_parse(const char* filename, ini_handler handler, void* user);
+
+/* Same as ini_parse(), but takes a FILE* instead of filename. This doesn't
+   close the file when it's finished -- the caller must do that. */
+int ini_parse_file(FILE* file, ini_handler handler, void* user);
+
+/* Same as ini_parse(), but takes an ini_reader function pointer instead of
+   filename. Used for implementing custom or string-based I/O (see also
+   ini_parse_string). */
+int ini_parse_stream(ini_reader reader, void* stream, ini_handler handler,
+                     void* user);
+
+/* Same as ini_parse(), but takes a zero-terminated string with the INI data
+instead of a file. Useful for parsing INI data from a network socket or
+already in memory. */
+int ini_parse_string(const char* string, ini_handler handler, void* user);
+
+/* Nonzero to allow multi-line value parsing, in the style of Python's
+   configparser. If allowed, ini_parse() will call the handler with the same
+   name for each subsequent line parsed. */
+#ifndef INI_ALLOW_MULTILINE
+#define INI_ALLOW_MULTILINE 1
+#endif
+
+/* Nonzero to allow a UTF-8 BOM sequence (0xEF 0xBB 0xBF) at the start of
+   the file. See http://code.google.com/p/inih/issues/detail?id=21 */
+#ifndef INI_ALLOW_BOM
+#define INI_ALLOW_BOM 1
+#endif
+
+/* Chars that begin a start-of-line comment. Per Python configparser, allow
+   both ; and # comments at the start of a line by default. */
+#ifndef INI_START_COMMENT_PREFIXES
+#define INI_START_COMMENT_PREFIXES ";#"
+#endif
+
+/* Nonzero to allow inline comments (with valid inline comment characters
+   specified by INI_INLINE_COMMENT_PREFIXES). Set to 0 to turn off and match
+   Python 3.2+ configparser behaviour. */
+#ifndef INI_ALLOW_INLINE_COMMENTS
+#define INI_ALLOW_INLINE_COMMENTS 1
+#endif
+#ifndef INI_INLINE_COMMENT_PREFIXES
+#define INI_INLINE_COMMENT_PREFIXES ";"
+#endif
+
+/* Nonzero to use stack for line buffer, zero to use heap (malloc/free). */
+#ifndef INI_USE_STACK
+#define INI_USE_STACK 1
+#endif
+
+/* Maximum line length for any line in INI file (stack or heap). Note that
+   this must be 3 more than the longest line (due to '\r', '\n', and '\0'). */
+#ifndef INI_MAX_LINE
+#define INI_MAX_LINE 200
+#endif
+
+/* Nonzero to allow heap line buffer to grow via realloc(), zero for a
+   fixed-size buffer of INI_MAX_LINE bytes. Only applies if INI_USE_STACK is
+   zero. */
+#ifndef INI_ALLOW_REALLOC
+#define INI_ALLOW_REALLOC 0
+#endif
+
+/* Initial size in bytes for heap line buffer. Only applies if INI_USE_STACK
+   is zero. */
+#ifndef INI_INITIAL_ALLOC
+#define INI_INITIAL_ALLOC 200
+#endif
+
+/* Stop parsing on first error (default is to keep parsing). */
+#ifndef INI_STOP_ON_FIRST_ERROR
+#define INI_STOP_ON_FIRST_ERROR 0
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __INI_H__ */

source/util/lz4.h

@@ -0,0 +1,569 @@
+/*
+ *  LZ4 - Fast LZ compression algorithm
+ *  Header File
+ *  Copyright (C) 2011-2017, Yann Collet.
+
+   BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are
+   met:
+
+       * Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+       * Redistributions in binary form must reproduce the above
+   copyright notice, this list of conditions and the following disclaimer
+   in the documentation and/or other materials provided with the
+   distribution.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+   You can contact the author at :
+    - LZ4 homepage : http://www.lz4.org
+    - LZ4 source repository : https://github.com/lz4/lz4
+*/
+#if defined (__cplusplus)
+extern "C" {
+#endif
+
+#ifndef LZ4_H_2983827168210
+#define LZ4_H_2983827168210
+
+/* --- Dependency --- */
+#include <stddef.h>   /* size_t */
+
+
+/**
+  Introduction
+
+  LZ4 is lossless compression algorithm, providing compression speed at 400 MB/s per core,
+  scalable with multi-cores CPU. It features an extremely fast decoder, with speed in
+  multiple GB/s per core, typically reaching RAM speed limits on multi-core systems.
+
+  The LZ4 compression library provides in-memory compression and decompression functions.
+  Compression can be done in:
+    - a single step (described as Simple Functions)
+    - a single step, reusing a context (described in Advanced Functions)
+    - unbounded multiple steps (described as Streaming compression)
+
+  lz4.h provides block compression functions. It gives full buffer control to user.
+  Decompressing an lz4-compressed block also requires metadata (such as compressed size).
+  Each application is free to encode such metadata in whichever way it wants.
+
+  An additional format, called LZ4 frame specification (doc/lz4_Frame_format.md),
+  take care of encoding standard metadata alongside LZ4-compressed blocks.
+  If your application requires interoperability, it's recommended to use it.
+  A library is provided to take care of it, see lz4frame.h.
+*/
+
+/*^***************************************************************
+*  Export parameters
+*****************************************************************/
+/*
+*  LZ4_DLL_EXPORT :
+*  Enable exporting of functions when building a Windows DLL
+*  LZ4LIB_VISIBILITY :
+*  Control library symbols visibility.
+*/
+#ifndef LZ4LIB_VISIBILITY
+#  if defined(__GNUC__) && (__GNUC__ >= 4)
+#    define LZ4LIB_VISIBILITY __attribute__ ((visibility ("default")))
+#  else
+#    define LZ4LIB_VISIBILITY
+#  endif
+#endif
+#if defined(LZ4_DLL_EXPORT) && (LZ4_DLL_EXPORT==1)
+#  define LZ4LIB_API __declspec(dllexport) LZ4LIB_VISIBILITY
+#elif defined(LZ4_DLL_IMPORT) && (LZ4_DLL_IMPORT==1)
+#  define LZ4LIB_API __declspec(dllimport) LZ4LIB_VISIBILITY /* It isn't required but allows to generate better code, saving a function pointer load from the IAT and an indirect jump.*/
+#else
+#  define LZ4LIB_API LZ4LIB_VISIBILITY
+#endif
+
+/*------   Version   ------*/
+#define LZ4_VERSION_MAJOR    1    /* for breaking interface changes  */
+#define LZ4_VERSION_MINOR    8    /* for new (non-breaking) interface capabilities */
+#define LZ4_VERSION_RELEASE  2    /* for tweaks, bug-fixes, or development */
+
+#define LZ4_VERSION_NUMBER (LZ4_VERSION_MAJOR *100*100 + LZ4_VERSION_MINOR *100 + LZ4_VERSION_RELEASE)
+
+#define LZ4_LIB_VERSION LZ4_VERSION_MAJOR.LZ4_VERSION_MINOR.LZ4_VERSION_RELEASE
+#define LZ4_QUOTE(str) #str
+#define LZ4_EXPAND_AND_QUOTE(str) LZ4_QUOTE(str)
+#define LZ4_VERSION_STRING LZ4_EXPAND_AND_QUOTE(LZ4_LIB_VERSION)
+
+LZ4LIB_API int LZ4_versionNumber (void);  /**< library version number; useful to check dll version */
+LZ4LIB_API const char* LZ4_versionString (void);   /**< library version string; unseful to check dll version */
+
+
+/*-************************************
+*  Tuning parameter
+**************************************/
+/*!
+ * LZ4_MEMORY_USAGE :
+ * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.)
+ * Increasing memory usage improves compression ratio
+ * Reduced memory usage may improve speed, thanks to cache effect
+ * Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache
+ */
+#ifndef LZ4_MEMORY_USAGE
+# define LZ4_MEMORY_USAGE 14
+#endif
+
+/*-************************************
+*  Simple Functions
+**************************************/
+/*! LZ4_compress_default() :
+    Compresses 'srcSize' bytes from buffer 'src'
+    into already allocated 'dst' buffer of size 'dstCapacity'.
+    Compression is guaranteed to succeed if 'dstCapacity' >= LZ4_compressBound(srcSize).
+    It also runs faster, so it's a recommended setting.
+    If the function cannot compress 'src' into a more limited 'dst' budget,
+    compression stops *immediately*, and the function result is zero.
+    Note : as a consequence, 'dst' content is not valid.
+    Note 2 : This function is protected against buffer overflow scenarios (never writes outside 'dst' buffer, nor read outside 'source' buffer).
+        srcSize : max supported value is LZ4_MAX_INPUT_SIZE.
+        dstCapacity : size of buffer 'dst' (which must be already allocated)
+        return  : the number of bytes written into buffer 'dst' (necessarily <= dstCapacity)
+                  or 0 if compression fails */
+LZ4LIB_API int LZ4_compress_default(const char* src, char* dst, int srcSize, int dstCapacity);
+
+/*! LZ4_decompress_safe() :
+    compressedSize : is the exact complete size of the compressed block.
+    dstCapacity : is the size of destination buffer, which must be already allocated.
+    return : the number of bytes decompressed into destination buffer (necessarily <= dstCapacity)
+             If destination buffer is not large enough, decoding will stop and output an error code (negative value).
+             If the source stream is detected malformed, the function will stop decoding and return a negative result.
+             This function is protected against malicious data packets.
+*/
+LZ4LIB_API int LZ4_decompress_safe (const char* src, char* dst, int compressedSize, int dstCapacity);
+
+
+/*-************************************
+*  Advanced Functions
+**************************************/
+#define LZ4_MAX_INPUT_SIZE        0x7E000000   /* 2 113 929 216 bytes */
+#define LZ4_COMPRESSBOUND(isize)  ((unsigned)(isize) > (unsigned)LZ4_MAX_INPUT_SIZE ? 0 : (isize) + ((isize)/255) + 16)
+
+/*!
+LZ4_compressBound() :
+    Provides the maximum size that LZ4 compression may output in a "worst case" scenario (input data not compressible)
+    This function is primarily useful for memory allocation purposes (destination buffer size).
+    Macro LZ4_COMPRESSBOUND() is also provided for compilation-time evaluation (stack memory allocation for example).
+    Note that LZ4_compress_default() compresses faster when dstCapacity is >= LZ4_compressBound(srcSize)
+        inputSize  : max supported value is LZ4_MAX_INPUT_SIZE
+        return : maximum output size in a "worst case" scenario
+              or 0, if input size is incorrect (too large or negative)
+*/
+LZ4LIB_API int LZ4_compressBound(int inputSize);
+
+/*!
+LZ4_compress_fast() :
+    Same as LZ4_compress_default(), but allows selection of "acceleration" factor.
+    The larger the acceleration value, the faster the algorithm, but also the lesser the compression.
+    It's a trade-off. It can be fine tuned, with each successive value providing roughly +~3% to speed.
+    An acceleration value of "1" is the same as regular LZ4_compress_default()
+    Values <= 0 will be replaced by ACCELERATION_DEFAULT (currently == 1, see lz4.c).
+*/
+LZ4LIB_API int LZ4_compress_fast (const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
+
+
+/*!
+LZ4_compress_fast_extState() :
+    Same compression function, just using an externally allocated memory space to store compression state.
+    Use LZ4_sizeofState() to know how much memory must be allocated,
+    and allocate it on 8-bytes boundaries (using malloc() typically).
+    Then, provide it as 'void* state' to compression function.
+*/
+LZ4LIB_API int LZ4_sizeofState(void);
+LZ4LIB_API int LZ4_compress_fast_extState (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
+
+
+/*!
+LZ4_compress_destSize() :
+    Reverse the logic : compresses as much data as possible from 'src' buffer
+    into already allocated buffer 'dst' of size 'targetDestSize'.
+    This function either compresses the entire 'src' content into 'dst' if it's large enough,
+    or fill 'dst' buffer completely with as much data as possible from 'src'.
+        *srcSizePtr : will be modified to indicate how many bytes where read from 'src' to fill 'dst'.
+                      New value is necessarily <= old value.
+        return : Nb bytes written into 'dst' (necessarily <= targetDestSize)
+                 or 0 if compression fails
+*/
+LZ4LIB_API int LZ4_compress_destSize (const char* src, char* dst, int* srcSizePtr, int targetDstSize);
+
+
+/*!
+LZ4_decompress_fast() : **unsafe!**
+This function is a bit faster than LZ4_decompress_safe(),
+but doesn't provide any security guarantee.
+    originalSize : is the uncompressed size to regenerate
+                   Destination buffer must be already allocated, and its size must be >= 'originalSize' bytes.
+    return : number of bytes read from source buffer (== compressed size).
+             If the source stream is detected malformed, the function stops decoding and return a negative result.
+    note : This function respects memory boundaries for *properly formed* compressed data.
+           However, it does not provide any protection against malicious input.
+           It also doesn't know 'src' size, and implies it's >= compressed size.
+           Use this function in trusted environment **only**.
+*/
+LZ4LIB_API int LZ4_decompress_fast (const char* src, char* dst, int originalSize);
+
+/*!
+LZ4_decompress_safe_partial() :
+    This function decompress a compressed block of size 'srcSize' at position 'src'
+    into destination buffer 'dst' of size 'dstCapacity'.
+    The function will decompress a minimum of 'targetOutputSize' bytes, and stop after that.
+    However, it's not accurate, and may write more than 'targetOutputSize' (but always <= dstCapacity).
+   @return : the number of bytes decoded in the destination buffer (necessarily <= dstCapacity)
+        Note : this number can also be < targetOutputSize, if compressed block contains less data.
+            Therefore, always control how many bytes were decoded.
+            If source stream is detected malformed, function returns a negative result.
+            This function is protected against malicious data packets.
+*/
+LZ4LIB_API int LZ4_decompress_safe_partial (const char* src, char* dst, int srcSize, int targetOutputSize, int dstCapacity);
+
+
+/*-*********************************************
+*  Streaming Compression Functions
+***********************************************/
+typedef union LZ4_stream_u LZ4_stream_t;  /* incomplete type (defined later) */
+
+/*! LZ4_createStream() and LZ4_freeStream() :
+ *  LZ4_createStream() will allocate and initialize an `LZ4_stream_t` structure.
+ *  LZ4_freeStream() releases its memory.
+ */
+LZ4LIB_API LZ4_stream_t* LZ4_createStream(void);
+LZ4LIB_API int           LZ4_freeStream (LZ4_stream_t* streamPtr);
+
+/*! LZ4_resetStream() :
+ *  An LZ4_stream_t structure can be allocated once and re-used multiple times.
+ *  Use this function to start compressing a new stream.
+ */
+LZ4LIB_API void LZ4_resetStream (LZ4_stream_t* streamPtr);
+
+/*! LZ4_loadDict() :
+ *  Use this function to load a static dictionary into LZ4_stream_t.
+ *  Any previous data will be forgotten, only 'dictionary' will remain in memory.
+ *  Loading a size of 0 is allowed, and is the same as reset.
+ * @return : dictionary size, in bytes (necessarily <= 64 KB)
+ */
+LZ4LIB_API int LZ4_loadDict (LZ4_stream_t* streamPtr, const char* dictionary, int dictSize);
+
+/*! LZ4_compress_fast_continue() :
+ *  Compress 'src' content using data from previously compressed blocks, for better compression ratio.
+ *  'dst' buffer must be already allocated.
+ *  If dstCapacity >= LZ4_compressBound(srcSize), compression is guaranteed to succeed, and runs faster.
+ *
+ *  Important : The previous 64KB of compressed data is assumed to remain present and unmodified in memory!
+ *
+ *  Special 1 : When input is a double-buffer, they can have any size, including < 64 KB.
+ *              Make sure that buffers are separated by at least one byte.
+ *              This way, each block only depends on previous block.
+ *  Special 2 : If input buffer is a ring-buffer, it can have any size, including < 64 KB.
+ *
+ * @return : size of compressed block
+ *           or 0 if there is an error (typically, cannot fit into 'dst').
+ *  After an error, the stream status is invalid, it can only be reset or freed.
+ */
+LZ4LIB_API int LZ4_compress_fast_continue (LZ4_stream_t* streamPtr, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
+
+/*! LZ4_saveDict() :
+ *  If last 64KB data cannot be guaranteed to remain available at its current memory location,
+ *  save it into a safer place (char* safeBuffer).
+ *  This is schematically equivalent to a memcpy() followed by LZ4_loadDict(),
+ *  but is much faster, because LZ4_saveDict() doesn't need to rebuild tables.
+ * @return : saved dictionary size in bytes (necessarily <= maxDictSize), or 0 if error.
+ */
+LZ4LIB_API int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int maxDictSize);
+
+
+/*-**********************************************
+*  Streaming Decompression Functions
+*  Bufferless synchronous API
+************************************************/
+typedef union LZ4_streamDecode_u LZ4_streamDecode_t;   /* incomplete type (defined later) */
+
+/*! LZ4_createStreamDecode() and LZ4_freeStreamDecode() :
+ *  creation / destruction of streaming decompression tracking structure.
+ *  A tracking structure can be re-used multiple times sequentially. */
+LZ4LIB_API LZ4_streamDecode_t* LZ4_createStreamDecode(void);
+LZ4LIB_API int                 LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream);
+
+/*! LZ4_setStreamDecode() :
+ *  An LZ4_streamDecode_t structure can be allocated once and re-used multiple times.
+ *  Use this function to start decompression of a new stream of blocks.
+ *  A dictionary can optionnally be set. Use NULL or size 0 for a reset order.
+ * @return : 1 if OK, 0 if error
+ */
+LZ4LIB_API int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize);
+
+/*! LZ4_decompress_*_continue() :
+ *  These decoding functions allow decompression of consecutive blocks in "streaming" mode.
+ *  A block is an unsplittable entity, it must be presented entirely to a decompression function.
+ *  Decompression functions only accept one block at a time.
+ *  The last 64KB of previously decoded data *must* remain available and unmodified at the memory position where they were decoded.
+ *  If less than 64KB of data has been decoded all the data must be present.
+ *
+ *  Special : if application sets a ring buffer for decompression, it must respect one of the following conditions :
+ *  - Exactly same size as encoding buffer, with same update rule (block boundaries at same positions)
+ *    In which case, the decoding & encoding ring buffer can have any size, including very small ones ( < 64 KB).
+ *  - Larger than encoding buffer, by a minimum of maxBlockSize more bytes.
+ *    maxBlockSize is implementation dependent. It's the maximum size of any single block.
+ *    In which case, encoding and decoding buffers do not need to be synchronized,
+ *    and encoding ring buffer can have any size, including small ones ( < 64 KB).
+ *  - _At least_ 64 KB + 8 bytes + maxBlockSize.
+ *    In which case, encoding and decoding buffers do not need to be synchronized,
+ *    and encoding ring buffer can have any size, including larger than decoding buffer.
+ *  Whenever these conditions are not possible, save the last 64KB of decoded data into a safe buffer,
+ *  and indicate where it is saved using LZ4_setStreamDecode() before decompressing next block.
+*/
+LZ4LIB_API int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int srcSize, int dstCapacity);
+LZ4LIB_API int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int originalSize);
+
+
+/*! LZ4_decompress_*_usingDict() :
+ *  These decoding functions work the same as
+ *  a combination of LZ4_setStreamDecode() followed by LZ4_decompress_*_continue()
+ *  They are stand-alone, and don't need an LZ4_streamDecode_t structure.
+ */
+LZ4LIB_API int LZ4_decompress_safe_usingDict (const char* src, char* dst, int srcSize, int dstCapcity, const char* dictStart, int dictSize);
+LZ4LIB_API int LZ4_decompress_fast_usingDict (const char* src, char* dst, int originalSize, const char* dictStart, int dictSize);
+
+
+/*^**********************************************
+ * !!!!!!   STATIC LINKING ONLY   !!!!!!
+ ***********************************************/
+
+/*-************************************
+ *  Unstable declarations
+ **************************************
+ * Declarations in this section should be considered unstable.
+ * Use at your own peril, etc., etc.
+ * They may be removed in the future.
+ * Their signatures may change.
+ **************************************/
+
+#ifdef LZ4_STATIC_LINKING_ONLY
+
+/*! LZ4_resetStream_fast() :
+ *  When an LZ4_stream_t is known to be in a internally coherent state,
+ *  it can often be prepared for a new compression with almost no work, only
+ *  sometimes falling back to the full, expensive reset that is always required
+ *  when the stream is in an indeterminate state (i.e., the reset performed by
+ *  LZ4_resetStream()).
+ *
+ *  LZ4_streams are guaranteed to be in a valid state when:
+ *  - returned from LZ4_createStream()
+ *  - reset by LZ4_resetStream()
+ *  - memset(stream, 0, sizeof(LZ4_stream_t))
+ *  - the stream was in a valid state and was reset by LZ4_resetStream_fast()
+ *  - the stream was in a valid state and was then used in any compression call
+ *    that returned success
+ *  - the stream was in an indeterminate state and was used in a compression
+ *    call that fully reset the state (LZ4_compress_fast_extState()) and that
+ *    returned success
+ */
+LZ4LIB_API void LZ4_resetStream_fast (LZ4_stream_t* streamPtr);
+
+/*! LZ4_compress_fast_extState_fastReset() :
+ *  A variant of LZ4_compress_fast_extState().
+ *
+ *  Using this variant avoids an expensive initialization step. It is only safe
+ *  to call if the state buffer is known to be correctly initialized already
+ *  (see above comment on LZ4_resetStream_fast() for a definition of "correctly
+ *  initialized"). From a high level, the difference is that this function
+ *  initializes the provided state with a call to LZ4_resetStream_fast() while
+ *  LZ4_compress_fast_extState() starts with a call to LZ4_resetStream().
+ */
+LZ4LIB_API int LZ4_compress_fast_extState_fastReset (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
+
+/*! LZ4_attach_dictionary() :
+ *  This is an experimental API that allows for the efficient use of a
+ *  static dictionary many times.
+ *
+ *  Rather than re-loading the dictionary buffer into a working context before
+ *  each compression, or copying a pre-loaded dictionary's LZ4_stream_t into a
+ *  working LZ4_stream_t, this function introduces a no-copy setup mechanism,
+ *  in which the working stream references the dictionary stream in-place.
+ *
+ *  Several assumptions are made about the state of the dictionary stream.
+ *  Currently, only streams which have been prepared by LZ4_loadDict() should
+ *  be expected to work.
+ *
+ *  Alternatively, the provided dictionary stream pointer may be NULL, in which
+ *  case any existing dictionary stream is unset.
+ *
+ *  If a dictionary is provided, it replaces any pre-existing stream history.
+ *  The dictionary contents are the only history that can be referenced and
+ *  logically immediately precede the data compressed in the first subsequent
+ *  compression call.
+ *
+ *  The dictionary will only remain attached to the working stream through the
+ *  first compression call, at the end of which it is cleared. The dictionary
+ *  stream (and source buffer) must remain in-place / accessible / unchanged
+ *  through the completion of the first compression call on the stream.
+ */
+LZ4LIB_API void LZ4_attach_dictionary(LZ4_stream_t *working_stream, const LZ4_stream_t *dictionary_stream);
+
+#endif
+
+/*-************************************
+ *  Private definitions
+ **************************************
+ * Do not use these definitions.
+ * They are exposed to allow static allocation of `LZ4_stream_t` and `LZ4_streamDecode_t`.
+ * Using these definitions will expose code to API and/or ABI break in future versions of the library.
+ **************************************/
+#define LZ4_HASHLOG   (LZ4_MEMORY_USAGE-2)
+#define LZ4_HASHTABLESIZE (1 << LZ4_MEMORY_USAGE)
+#define LZ4_HASH_SIZE_U32 (1 << LZ4_HASHLOG)       /* required as macro for static allocation */
+
+#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
+#include <stdint.h>
+
+typedef struct LZ4_stream_t_internal LZ4_stream_t_internal;
+struct LZ4_stream_t_internal {
+    uint32_t hashTable[LZ4_HASH_SIZE_U32];
+    uint32_t currentOffset;
+    uint16_t initCheck;
+    uint16_t tableType;
+    const uint8_t* dictionary;
+    const LZ4_stream_t_internal* dictCtx;
+    uint32_t dictSize;
+};
+
+typedef struct {
+    const uint8_t* externalDict;
+    size_t extDictSize;
+    const uint8_t* prefixEnd;
+    size_t prefixSize;
+} LZ4_streamDecode_t_internal;
+
+#else
+
+typedef struct LZ4_stream_t_internal LZ4_stream_t_internal;
+struct LZ4_stream_t_internal {
+    unsigned int hashTable[LZ4_HASH_SIZE_U32];
+    unsigned int currentOffset;
+    unsigned short initCheck;
+    unsigned short tableType;
+    const unsigned char* dictionary;
+    const LZ4_stream_t_internal* dictCtx;
+    unsigned int dictSize;
+};
+
+typedef struct {
+    const unsigned char* externalDict;
+    size_t extDictSize;
+    const unsigned char* prefixEnd;
+    size_t prefixSize;
+} LZ4_streamDecode_t_internal;
+
+#endif
+
+/*!
+ * LZ4_stream_t :
+ * information structure to track an LZ4 stream.
+ * init this structure before first use.
+ * note : only use in association with static linking !
+ *        this definition is not API/ABI safe,
+ *        it may change in a future version !
+ */
+#define LZ4_STREAMSIZE_U64 ((1 << (LZ4_MEMORY_USAGE-3)) + 4)
+#define LZ4_STREAMSIZE     (LZ4_STREAMSIZE_U64 * sizeof(unsigned long long))
+union LZ4_stream_u {
+    unsigned long long table[LZ4_STREAMSIZE_U64];
+    LZ4_stream_t_internal internal_donotuse;
+} ;  /* previously typedef'd to LZ4_stream_t */
+
+
+/*!
+ * LZ4_streamDecode_t :
+ * information structure to track an LZ4 stream during decompression.
+ * init this structure  using LZ4_setStreamDecode (or memset()) before first use
+ * note : only use in association with static linking !
+ *        this definition is not API/ABI safe,
+ *        and may change in a future version !
+ */
+#define LZ4_STREAMDECODESIZE_U64  4
+#define LZ4_STREAMDECODESIZE     (LZ4_STREAMDECODESIZE_U64 * sizeof(unsigned long long))
+union LZ4_streamDecode_u {
+    unsigned long long table[LZ4_STREAMDECODESIZE_U64];
+    LZ4_streamDecode_t_internal internal_donotuse;
+} ;   /* previously typedef'd to LZ4_streamDecode_t */
+
+
+/*-************************************
+*  Obsolete Functions
+**************************************/
+
+/*! Deprecation warnings
+   Should deprecation warnings be a problem,
+   it is generally possible to disable them,
+   typically with -Wno-deprecated-declarations for gcc
+   or _CRT_SECURE_NO_WARNINGS in Visual.
+   Otherwise, it's also possible to define LZ4_DISABLE_DEPRECATE_WARNINGS */
+#ifdef LZ4_DISABLE_DEPRECATE_WARNINGS
+#  define LZ4_DEPRECATED(message)   /* disable deprecation warnings */
+#else
+#  define LZ4_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
+#  if defined (__cplusplus) && (__cplusplus >= 201402) /* C++14 or greater */
+#    define LZ4_DEPRECATED(message) [[deprecated(message)]]
+#  elif (LZ4_GCC_VERSION >= 405) || defined(__clang__)
+#    define LZ4_DEPRECATED(message) __attribute__((deprecated(message)))
+#  elif (LZ4_GCC_VERSION >= 301)
+#    define LZ4_DEPRECATED(message) __attribute__((deprecated))
+#  elif defined(_MSC_VER)
+#    define LZ4_DEPRECATED(message) __declspec(deprecated(message))
+#  else
+#    pragma message("WARNING: You need to implement LZ4_DEPRECATED for this compiler")
+#    define LZ4_DEPRECATED(message)
+#  endif
+#endif /* LZ4_DISABLE_DEPRECATE_WARNINGS */
+
+/* Obsolete compression functions */
+LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress               (const char* source, char* dest, int sourceSize);
+LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress_limitedOutput (const char* source, char* dest, int sourceSize, int maxOutputSize);
+LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") LZ4LIB_API int LZ4_compress_withState               (void* state, const char* source, char* dest, int inputSize);
+LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") LZ4LIB_API int LZ4_compress_limitedOutput_withState (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
+LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") LZ4LIB_API int LZ4_compress_continue                (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize);
+LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") LZ4LIB_API int LZ4_compress_limitedOutput_continue  (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize, int maxOutputSize);
+
+/* Obsolete decompression functions */
+LZ4_DEPRECATED("use LZ4_decompress_fast() instead") LZ4LIB_API int LZ4_uncompress (const char* source, char* dest, int outputSize);
+LZ4_DEPRECATED("use LZ4_decompress_safe() instead") LZ4LIB_API int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize);
+
+/* Obsolete streaming functions; degraded functionality; do not use!
+ *
+ * In order to perform streaming compression, these functions depended on data
+ * that is no longer tracked in the state. They have been preserved as well as
+ * possible: using them will still produce a correct output. However, they don't
+ * actually retain any history between compression calls. The compression ratio
+ * achieved will therefore be no better than compressing each chunk
+ * independently.
+ */
+LZ4_DEPRECATED("Use LZ4_createStream() instead") LZ4LIB_API void* LZ4_create (char* inputBuffer);
+LZ4_DEPRECATED("Use LZ4_createStream() instead") LZ4LIB_API int   LZ4_sizeofStreamState(void);
+LZ4_DEPRECATED("Use LZ4_resetStream() instead") LZ4LIB_API  int   LZ4_resetStreamState(void* state, char* inputBuffer);
+LZ4_DEPRECATED("Use LZ4_saveDict() instead") LZ4LIB_API     char* LZ4_slideInputBuffer (void* state);
+
+/* Obsolete streaming decoding functions */
+LZ4_DEPRECATED("use LZ4_decompress_safe_usingDict() instead") LZ4LIB_API int LZ4_decompress_safe_withPrefix64k (const char* src, char* dst, int compressedSize, int maxDstSize);
+LZ4_DEPRECATED("use LZ4_decompress_fast_usingDict() instead") LZ4LIB_API int LZ4_decompress_fast_withPrefix64k (const char* src, char* dst, int originalSize);
+
+#endif /* LZ4_H_2983827168210 */
+
+
+#if defined (__cplusplus)
+}
+#endif

source/util/util_compression.cpp

@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2018-2019 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <switch.h>
+#include <stratosphere.hpp>
+#include <stratosphere/util.hpp>
+
+#include "lz4.h"
+
+namespace sts::util {
+
+    /* Compression utilities. */
+    int CompressLZ4(void *dst, size_t dst_size, const void *src, size_t src_size) {
+        /* Size checks. */
+        if (dst_size > std::numeric_limits<int>::max() || src_size > std::numeric_limits<int>::max()) {
+            std::abort();
+        }
+
+        /* This is just a thin wrapper around LZ4. */
+        return LZ4_compress_default(reinterpret_cast<const char *>(src), reinterpret_cast<char *>(dst), static_cast<int>(src_size), static_cast<int>(dst_size));
+    }
+
+    /* Decompression utilities. */
+    int DecompressLZ4(void *dst, size_t dst_size, const void *src, size_t src_size) {
+        /* Size checks. */
+        if (dst_size > std::numeric_limits<int>::max() || src_size > std::numeric_limits<int>::max()) {
+            std::abort();
+        }
+
+        /* This is just a thin wrapper around LZ4. */
+        return LZ4_decompress_safe(reinterpret_cast<const char *>(src), reinterpret_cast<char *>(dst), static_cast<int>(src_size), static_cast<int>(dst_size));
+    }
+
+}

source/util/util_ini.cpp

@@ -0,0 +1,96 @@
+/*
+ * Copyright (c) 2018-2019 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <switch.h>
+#include <stratosphere.hpp>
+#include <stratosphere/util.hpp>
+
+#include "ini.h"
+
+namespace sts::util::ini {
+
+    /* Ensure that types are the same for Handler vs ini_handler. */
+    static_assert(std::is_same<Handler, ::ini_handler>::value, "Bad ini::Handler definition!");
+
+    namespace {
+
+        struct FsFileContext {
+            FsFile *f;
+            size_t offset;
+            size_t num_left;
+
+            explicit FsFileContext(FsFile *f) : f(f), offset(0) {
+                u64 size;
+                R_ASSERT(fsFileGetSize(this->f, &size));
+                this->num_left = size_t(size);
+            }
+        };
+
+        char *ini_reader_fs_file(char *str, int num, void *stream) {
+            FsFileContext *ctx = reinterpret_cast<FsFileContext *>(stream);
+
+            if (ctx->num_left == 0 || num < 2) {
+                return nullptr;
+            }
+
+            /* Read as many bytes as we can. */
+            size_t try_read = std::min(size_t(num - 1), ctx->num_left);
+            size_t actually_read;
+            R_ASSERT(fsFileRead(ctx->f, ctx->offset, str, try_read, FS_READOPTION_NONE, &actually_read));
+            if (actually_read != try_read) {
+                std::abort();
+            }
+
+            /* Only "read" up to the first \n. */
+            size_t offset = actually_read;
+            for (size_t i = 0; i < actually_read; i++) {
+                if (str[i] == '\n') {
+                    offset = i + 1;
+                    break;
+                }
+            }
+
+            /* Ensure null termination. */
+            str[offset] = '\0';
+
+            /* Update context. */
+            ctx->offset += offset;
+            ctx->num_left -= offset;
+
+            return str;
+        }
+
+    }
+
+    /* Utilities for dealing with INI file configuration. */
+    int ParseString(const char *ini_str, void *user_ctx, Handler h) {
+        return ini_parse_string(ini_str, h, user_ctx);
+    }
+
+    int ParseFile(FILE *f, void *user_ctx, Handler h) {
+        return ini_parse_file(f, h, user_ctx);
+    }
+
+    int ParseFile(FsFile *f, void *user_ctx, Handler h) {
+        FsFileContext ctx(f);
+        return ini_parse_stream(ini_reader_fs_file, &ctx, h, user_ctx);
+    }
+
+    int ParseFile(const char *path, void *user_ctx, Handler h) {
+        return ini_parse(path, h, user_ctx);
+    }
+
+}