file.h File Reference

#include <stdio.h>
#include <sys/stat.h>
#include <htils/arena.h>
#include <htils/basictypes.h>
#include <htils/string.h>

Go to the source code of this file.

Functions
u64	file_size_stream (FILE *stream)
	Gets the size of a file from a file stream.
u64	file_size (const string *path)
	Gets the size of a file at path.
string *	read_file_from_stream (arena_t *arena, FILE *stream)
	Reads the contents of a file from stream into a string.
string *	read_file (arena_t *arena, const string *path)
	Reads the contents of a file at path into a string.
string *	read_file_from_stream_bytes (arena_t *arena, FILE *stream, const u64 bytes)
	Read bytes from file stream to string.
string *	read_file_bytes (arena_t *arena, const string *path, const u64 bytes)
	Read bytes from a file path to string.
u64	write_to_file_stream (FILE *stream, const string *contents)
	Write contents to file stream.
u64	write_to_file (const string *path, const string *contents)
	Write contents to file path.
u64	write_to_file_stream_bytes (FILE *stream, const string *contents, const u64 bytes)
	Write bytes from contents to stream.
u64	write_to_file_bytes (const string *path, const string *contents, const u64 bytes)
	Write bytes from contents to a file at path.

Function Documentation

file_size()

u64 file_size

(

const string *

path

)

Gets the size of a file at path.

Opens the file and defers to file_size_stream().

Precondition

path must be valid and cannot be null.

Parameters

path	The path to the file to get the size of.

Returns

The size of the file.

See also

file_size_stream()

file_size_stream()

u64 file_size_stream

(

FILE *

stream

)

Gets the size of a file from a file stream.

Safe macros for fstat() and fileno() thats compatible across platforms.

By reading the size using fstat() by first converting the file stream into a file descriptor with fileno(). and then getting the stat structure's st_size field.

fstat() and fileno() are aliases:

• For Linux: Using fstat() and fileno().
• For Windows: Using _fstati64() and _fileno().

Precondition

stream must be valid, preferably open with "rb" and cannot be null.

Parameters

stream

The file stream to get the size of.

Returns

The size of the file.

See also

fstat(), fileno(), _fstati64(), _fileno().

read_file()

string * read_file	(	arena_t *	arena,
		const string *	path )

Reads the contents of a file at path into a string.

Opens the file and defers to read_file_from_stream().

Precondition

• arena and path must be valid and cannot be null.

Parameters

arena	For allocating the contents of the file.
path	The path to the file to read.

Returns

A string containing the contents of the file.

See also

read_file_from_stream()

read_file_bytes()

string * read_file_bytes	(	arena_t *	arena,
		const string *	path,
		const u64	bytes )

Read bytes from a file path to string.

By opening the file, reading bytes into a block using read_file_from_stream_bytes(), then returning the result.

Precondition

• arena, and path must be valid and cannot be null.
• bytes must be greater than 0.

Parameters

arena	For allocating the contents of the file.
path	The path to the file to read.
bytes	The number of bytes to read.

Returns

A string containing the contents of the file.

See also

read_file_from_stream_bytes()

read_file_from_stream()

string * read_file_from_stream	(	arena_t *	arena,
		FILE *	stream )

Reads the contents of a file from stream into a string.

Reads the stream to EOF and returns it as a string, with the byte count in the string's len, using fread().

Precondition

• arena must be valid, and cannot be null.
• stream must be valid, and cannot be null preferably open with "rb".

Parameters

arena	For allocating the contents of the file.
stream	The file stream to read from.

Returns

A string containing the contents of the file.

See also

fread()

read_file_from_stream_bytes()

string * read_file_from_stream_bytes	(	arena_t *	arena,
		FILE *	stream,
		const u64	bytes )

Read bytes from file stream to string.

By allocating a block using the arena that is bytes big and reading bytes into that block using fread().

Precondition

• arena and stream must be valid and cannot be null.
• stream should be preferably open with "rb".
• bytes must be greater than 0.

Parameters

arena	For allocating the contents of the file.
stream	The file stream to read from.
bytes	The number of bytes to read.

Returns

A string containing the contents of the file.

See also

fread()

write_to_file()

u64 write_to_file	(	const string *	path,
		const string *	contents )

Write contents to file path.

By writing len characters from contents to the file at path using write_to_file_stream().

Precondition

path and contents must be valid, and cannot be null.

Parameters

path	The path to the file to write to.
contents	The string to write to the file.

Returns

The number of bytes written.

See also

write_to_file_stream()

write_to_file_bytes()

u64 write_to_file_bytes	(	const string *	path,
		const string *	contents,
		const u64	bytes )

Write bytes from contents to a file at path.

By writing bytes from contents to the file at path using write_to_file_stream_bytes(), and then returning the result.

Precondition

• path and contents must be valid, and cannot be null.
• bytes must be greater than 0.

Parameters

path	The path to the file to write to.
contents	The string to write to the file.
bytes	The number of bytes to write.

Returns

The number of bytes written.

See also

write_to_file_stream_bytes()

write_to_file_stream()

u64 write_to_file_stream	(	FILE *	stream,
		const string *	contents )

Write contents to file stream.

By writing len characters from contents to that file thats associated with stream using fwrite().

Precondition

• stream and contents must be valid, and cannot be null.
• stream should be preferably open with "wb".

Parameters

stream	The file stream to write to.
contents	The string to write to the file.

Returns

The number of bytes written.

See also

fwrite()

write_to_file_stream_bytes()

u64 write_to_file_stream_bytes	(	FILE *	stream,
		const string *	contents,
		const u64	bytes )

Write bytes from contents to stream.

By writing bytes from contents to the file stream provided by stream using fwrite() .

Precondition

• stream, and contents must be valid, and cannot be null
• stream should be preferably open with "wb".
• bytes must be greater than 0.

Parameters

stream	The file stream to write to.
contents	The string to write to the file.
bytes	The number of bytes to write.

Returns

The number of bytes written.

See also

fwrite()