functions for buffering IO More...

#include "platform.h"
#include "gnunet_util_lib.h"

Include dependency graph for bio.c:

Data Structures
struct	GNUNET_BIO_ReadHandle
	Handle for buffered reading. More...

struct	GNUNET_BIO_WriteHandle
	Handle for buffered writing. More...

Macros
#define	LOG(kind, ...) GNUNET_log_from (kind, "util-bio", __VA_ARGS__)

#define	PATH_MAX 4096
	Assumed maximum path length (for source file names). More...

#define	BIO_BUFFER_SIZE 65536
	Size for I/O buffers. More...

Enumerations
enum	IOType { IO_FILE = 0 , IO_BUFFER }
	Enum used internally to know how buffering is handled. More...

Functions
struct GNUNET_BIO_ReadHandle *	GNUNET_BIO_read_open_file (const char *fn)
	Open a file for reading. More...

struct GNUNET_BIO_ReadHandle *	GNUNET_BIO_read_open_buffer (void *buffer, size_t size)
	Create a handle from an existing allocated buffer. More...

int	GNUNET_BIO_read_close (struct GNUNET_BIO_ReadHandle h, char *emsg)
	Close an open handle. More...

void	GNUNET_BIO_read_set_error (struct GNUNET_BIO_ReadHandle h, const char emsg)
	Set read error to handle. More...

static int	read_from_file (struct GNUNET_BIO_ReadHandle h, const char what, char *result, size_t len)
	Function used internally to read the contents of a file into a buffer. More...

static int	read_from_buffer (struct GNUNET_BIO_ReadHandle h, const char what, char *result, size_t len)
	Function used internally to read the content of a buffer into a buffer. More...

int	GNUNET_BIO_read (struct GNUNET_BIO_ReadHandle h, const char what, void *result, size_t len)
	Read some contents into a buffer. More...

int	GNUNET_BIO_read_string (struct GNUNET_BIO_ReadHandle h, const char what, char **result, size_t max_length)
	Read 0-terminated string. More...

int	GNUNET_BIO_read_float (struct GNUNET_BIO_ReadHandle h, const char what, float *f)
	Read a float. More...

int	GNUNET_BIO_read_double (struct GNUNET_BIO_ReadHandle h, const char what, double *f)
	Read a double. More...

int	GNUNET_BIO_read_int32 (struct GNUNET_BIO_ReadHandle h, const char what, int32_t *i)
	Read an (u)int32_t. More...

int	GNUNET_BIO_read_int64 (struct GNUNET_BIO_ReadHandle h, const char what, int64_t *i)
	Read an (u)int64_t. More...

struct GNUNET_BIO_WriteHandle *	GNUNET_BIO_write_open_file (const char *fn)
	Open a file for writing. More...

struct GNUNET_BIO_WriteHandle *	GNUNET_BIO_write_open_buffer (void)
	Create a handle backed by an in-memory buffer. More...

enum GNUNET_GenericReturnValue	GNUNET_BIO_write_close (struct GNUNET_BIO_WriteHandle h, char *emsg)
	Close an IO handle. More...

enum GNUNET_GenericReturnValue	GNUNET_BIO_flush (struct GNUNET_BIO_WriteHandle *h)
	Force a file-based buffered writer to flush its buffer. More...

enum GNUNET_GenericReturnValue	GNUNET_BIO_get_buffer_contents (struct GNUNET_BIO_WriteHandle h, char emsg, void contents, size_t size)
	Get the IO handle's contents. More...

static enum GNUNET_GenericReturnValue	write_to_file (struct GNUNET_BIO_WriteHandle h, const char what, const char *source, size_t len)
	Function used internally to write the contents of a buffer into a file. More...

static int	write_to_buffer (struct GNUNET_BIO_WriteHandle h, const char what, const char *source, size_t len)
	Function used internally to write the contents of a buffer to another buffer. More...

int	GNUNET_BIO_write (struct GNUNET_BIO_WriteHandle h, const char what, const void *buffer, size_t n)
	Write a buffer to a handle. More...

int	GNUNET_BIO_write_string (struct GNUNET_BIO_WriteHandle h, const char what, const char *s)
	Write a 0-terminated string. More...

int	GNUNET_BIO_write_float (struct GNUNET_BIO_WriteHandle h, const char what, float f)
	Write a float. More...

int	GNUNET_BIO_write_double (struct GNUNET_BIO_WriteHandle h, const char what, double f)
	Write a double. More...

int	GNUNET_BIO_write_int32 (struct GNUNET_BIO_WriteHandle h, const char what, int32_t i)
	Write an (u)int32_t. More...

int	GNUNET_BIO_write_int64 (struct GNUNET_BIO_WriteHandle h, const char what, int64_t i)
	Write an (u)int64_t. More...

static int	read_spec_handler_object (void cls, struct GNUNET_BIO_ReadHandle h, const char what, void target, size_t target_size)
	Function used internally to read some bytes from within a read spec. More...

struct GNUNET_BIO_ReadSpec	GNUNET_BIO_read_spec_object (const char what, void result, size_t len)
	Create the specification to read a certain amount of bytes. More...

static int	read_spec_handler_string (void cls, struct GNUNET_BIO_ReadHandle h, const char what, void target, size_t target_size)
	Function used internally to read a string from within a read spec. More...

struct GNUNET_BIO_ReadSpec	GNUNET_BIO_read_spec_string (const char what, char *result, size_t max_length)
	Create the specification to read a 0-terminated string. More...

static int	read_spec_handler_int32 (void cls, struct GNUNET_BIO_ReadHandle h, const char what, void target, size_t target_size)
	Function used internally to read an (u)int32_t from within a read spec. More...

struct GNUNET_BIO_ReadSpec	GNUNET_BIO_read_spec_int32 (const char what, int32_t i)
	Create the specification to read an (u)int32_t. More...

static int	read_spec_handler_int64 (void cls, struct GNUNET_BIO_ReadHandle h, const char what, void target, size_t target_size)
	Function used internally to read an (u)int64_t from within a read spec. More...

struct GNUNET_BIO_ReadSpec	GNUNET_BIO_read_spec_int64 (const char what, int64_t i)
	Create the specification to read an (u)int64_t. More...

struct GNUNET_BIO_ReadSpec	GNUNET_BIO_read_spec_float (const char what, float f)
	Create the specification to read a float. More...

struct GNUNET_BIO_ReadSpec	GNUNET_BIO_read_spec_double (const char what, double f)
	Create the specification to read a double. More...

int	GNUNET_BIO_read_spec_commit (struct GNUNET_BIO_ReadHandle h, struct GNUNET_BIO_ReadSpec rs)
	Execute the read specifications in order. More...

static int	write_spec_handler_object (void cls, struct GNUNET_BIO_WriteHandle h, const char what, void source, size_t source_size)
	Function used internally to write some bytes from within a write spec. More...

struct GNUNET_BIO_WriteSpec	GNUNET_BIO_write_spec_object (const char what, void source, size_t size)
	Create the specification to read some bytes. More...

static int	write_spec_handler_string (void cls, struct GNUNET_BIO_WriteHandle h, const char what, void source, size_t source_size)
	Function used internally to write a 0-terminated string from within a write spec. More...

struct GNUNET_BIO_WriteSpec	GNUNET_BIO_write_spec_string (const char what, const char s)
	Create the specification to write a 0-terminated string. More...

static int	write_spec_handler_int32 (void cls, struct GNUNET_BIO_WriteHandle h, const char what, void source, size_t source_size)
	Function used internally to write an (u)int32_t from within a write spec. More...

struct GNUNET_BIO_WriteSpec	GNUNET_BIO_write_spec_int32 (const char what, int32_t i)
	Create the specification to write an (u)int32_t. More...

static int	write_spec_handler_int64 (void cls, struct GNUNET_BIO_WriteHandle h, const char what, void source, size_t source_size)
	Function used internally to write an (u)int64_t from within a write spec. More...

struct GNUNET_BIO_WriteSpec	GNUNET_BIO_write_spec_int64 (const char what, int64_t i)
	Create the specification to write an (u)int64_t. More...

struct GNUNET_BIO_WriteSpec	GNUNET_BIO_write_spec_float (const char what, float f)
	Create the specification to write a float. More...

struct GNUNET_BIO_WriteSpec	GNUNET_BIO_write_spec_double (const char what, double f)
	Create the specification to write an double. More...

int	GNUNET_BIO_write_spec_commit (struct GNUNET_BIO_WriteHandle h, struct GNUNET_BIO_WriteSpec ws)
	Execute the write specifications in order. More...

Detailed Description

functions for buffering IO

Author: Christian Grothoff

Definition in file bio.c.

Macro Definition Documentation

◆ LOG

#define LOG	(	kind,
		...
	)	GNUNET_log_from (kind, "util-bio", __VA_ARGS__)

Definition at line 29 of file bio.c.

◆ PATH_MAX

#define PATH_MAX 4096

Assumed maximum path length (for source file names).

Definition at line 35 of file bio.c.

◆ BIO_BUFFER_SIZE

#define BIO_BUFFER_SIZE 65536

Size for I/O buffers.

Definition at line 42 of file bio.c.

Enumeration Type Documentation

◆ IOType

enum IOType

Enum used internally to know how buffering is handled.

The idea is that by using an enum, BIO can be extended to support other kinds of "backend" for buffering (or just formatted I/O.)

Enumerator
IO_FILE	The handle uses a file to read/write data.
IO_BUFFER	The data is stored entirely in memory.

Definition at line 51 of file bio.c.

 {
   IO_FILE = 0,
  
   IO_BUFFER,
 };

Function Documentation

◆ read_from_file()

static int read_from_file	(	struct GNUNET_BIO_ReadHandle *	h,
		const char *	what,
		char *	result,
		size_t	len
	)

static

Function used internally to read the contents of a file into a buffer.

Parameters

h	the IO handle to read from
what	describes what is being read (for error message creation)
result	the buffer to write the data to
len	the number of bytes to read

Returns: GNUNET_OK on success, GNUNET_SYSERR otherwise

Definition at line 204 of file bio.c.

 {
   size_t pos = 0;
   size_t min;
   ssize_t ret;
  
   do
   {
     min = h->have - h->pos;
     if (0 < min)
     {
       if (len - pos < min)
         min = len - pos;
       GNUNET_memcpy (&result[pos], &h->buffer[h->pos], min);
       h->pos += min;
       pos += min;
     }
     if (len == pos)
       return GNUNET_OK;
     GNUNET_assert (((off_t) h->have) == h->pos);
     ret = GNUNET_DISK_file_read (h->fd, h->buffer, h->size);
     if (-1 == ret)
     {
       GNUNET_asprintf (&h->emsg,
                        _ ("Error reading `%s' from file: %s"),
                        what,
                        strerror (errno));
       return GNUNET_SYSERR;
     }
     if (0 == ret)
     {
       GNUNET_asprintf (&h->emsg,
                        _ ("Error reading `%s' from file: %s"),
                        what,
                        _ ("End of file"));
       return GNUNET_SYSERR;
     }
     h->pos = 0;
     h->have = ret;
   }
   while (pos < len);
   return GNUNET_OK;
 }

References _, GNUNET_asprintf(), GNUNET_assert, GNUNET_DISK_file_read(), GNUNET_memcpy, GNUNET_OK, GNUNET_SYSERR, h, len, min, GNUNET_BIO_ReadHandle::pos, result, and ret.

Referenced by GNUNET_BIO_read().

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◆ read_from_buffer()

static int read_from_buffer	(	struct GNUNET_BIO_ReadHandle *	h,
		const char *	what,
		char *	result,
		size_t	len
	)

static

Function used internally to read the content of a buffer into a buffer.

Parameters

h	the IO handle to read from
what	describes what is being read (for error message creation)
result	the buffer to write the result to
len	the number of bytes to read

Returns: GNUNET_OK on success, GNUNET_SYSERR otherwise

Definition at line 262 of file bio.c.

 {
   if ((h->size < len) || (h->size - h->pos < len))
   {
     GNUNET_asprintf (&h->emsg,
                      _ ("Error while reading `%s' from buffer: %s"),
                      what,
                      _ ("Not enough data left"));
     return GNUNET_SYSERR;
   }
   GNUNET_memcpy (result, h->buffer + h->pos, len);
   h->pos += len;
   return GNUNET_OK;
 }

References _, GNUNET_asprintf(), GNUNET_memcpy, GNUNET_OK, GNUNET_SYSERR, h, len, and result.

Referenced by GNUNET_BIO_read().

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◆ write_to_file()

static enum GNUNET_GenericReturnValue write_to_file	(	struct GNUNET_BIO_WriteHandle *	h,
		const char *	what,
		const char *	source,
		size_t	len
	)

static

Function used internally to write the contents of a buffer into a file.

Parameters

h	the IO handle to write to
what	describes what is being written (for error message creation)
source	the buffer to write
len	the number of bytes to write

Returns: GNUNET_OK on success, GNUNET_SYSERR otherwise

Definition at line 535 of file bio.c.

 {
   size_t min;
   size_t pos = 0;
   char *buffer = (char *) h->buffer;
  
   if (NULL == h->fd)
   {
     GNUNET_asprintf (&h->emsg,
                      _ ("Error while writing `%s' to file: %s"),
                      what,
                      _ ("No associated file"));
     return GNUNET_SYSERR;
   }
  
   do
   {
     min = h->size - h->have;
     if (len - pos < min)
       min = len - pos;
     GNUNET_memcpy (&buffer[h->have], &source[pos], min);
     pos += min;
     h->have += min;
     if (len == pos)
       return GNUNET_OK;
     GNUNET_assert (h->have == h->size);
     if (GNUNET_OK != GNUNET_BIO_flush (h))
     {
       char *tmp = h->emsg;
       GNUNET_asprintf (&h->emsg,
                        _ ("Error while writing `%s' to file: %s"),
                        what,
                        tmp);
       GNUNET_free (tmp);
       return GNUNET_SYSERR;
     }
   }
   while (pos < len);
   GNUNET_break (0);
   return GNUNET_OK;
 }

Referenced by GNUNET_BIO_write().

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◆ write_to_buffer()

static int write_to_buffer	(	struct GNUNET_BIO_WriteHandle *	h,
		const char *	what,
		const char *	source,
		size_t	len
	)

static

Function used internally to write the contents of a buffer to another buffer.

Parameters

h	the IO handle to write to
what	describes what is being written (for error message creation)
source	the buffer to write
len	the number of bytes to write

Returns: GNUNET_OK on success, GNUNET_SYSERR otherwise

Definition at line 731 of file bio.c.

 {
   GNUNET_buffer_write ((struct GNUNET_Buffer *) h->buffer, source, len);
   h->have += len;
   return GNUNET_OK;
 }

References GNUNET_buffer_write(), GNUNET_OK, h, len, and source.

Referenced by GNUNET_BIO_write().

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◆ read_spec_handler_object()

static int read_spec_handler_object	(	void *	cls,
		struct GNUNET_BIO_ReadHandle *	h,
		const char *	what,
		void *	target,
		size_t	target_size
	)

static

Function used internally to read some bytes from within a read spec.

Parameters

cls	ignored, always NULL
h	the IO handle to read from
what	what is being read (for error message creation)
target	where to store the data
target_size	how many bytes to read

Returns: GNUNET_OK on success, GNUNET_SYSERR otherwise

Definition at line 889 of file bio.c.

 {
   return GNUNET_BIO_read (h, what, target, target_size);
 }

◆ read_spec_handler_string()

static int read_spec_handler_string	(	void *	cls,
		struct GNUNET_BIO_ReadHandle *	h,
		const char *	what,
		void *	target,
		size_t	target_size
	)

static

Function used internally to read a string from within a read spec.

Parameters

cls	ignored, always NULL
h	the IO handle to read from
what	what is being read (for error message creation)
target	where to store the data
target_size	how many bytes to read

Returns: GNUNET_OK on success, GNUNET_SYSERR otherwise

Definition at line 935 of file bio.c.

 {
   char **result = target;
   return GNUNET_BIO_read_string (h, what, result, target_size);
 }

◆ read_spec_handler_int32()

static int read_spec_handler_int32	(	void *	cls,
		struct GNUNET_BIO_ReadHandle *	h,
		const char *	what,
		void *	target,
		size_t	target_size
	)

static

Function used internally to read an (u)int32_t from within a read spec.

Parameters

cls	ignored, always NULL
h	the IO handle to read from
what	what is being read (for error message creation)
target	where to store the data
target_size	ignored

Returns: GNUNET_OK on success, GNUNET_SYSERR otherwise

Definition at line 982 of file bio.c.

 {
   int32_t *result = target;
   return GNUNET_BIO_read_int32 (h, what, result);
 }

◆ read_spec_handler_int64()

static int read_spec_handler_int64	(	void *	cls,
		struct GNUNET_BIO_ReadHandle *	h,
		const char *	what,
		void *	target,
		size_t	target_size
	)

static

Function used internally to read an (u)int64_t from within a read spec.

Parameters

cls	ignored, always NULL
h	the IO handle to read from
what	what is being read (for error message creation)
target	where to store the data
target_size	ignored

Returns: GNUNET_OK on success, GNUNET_SYSERR otherwise

Definition at line 1026 of file bio.c.

 {
   int64_t *result = target;
   return GNUNET_BIO_read_int64 (h, what, result);
 }

◆ write_spec_handler_object()

static int write_spec_handler_object	(	void *	cls,
		struct GNUNET_BIO_WriteHandle *	h,
		const char *	what,
		void *	source,
		size_t	source_size
	)

static

Function used internally to write some bytes from within a write spec.

Parameters

cls	ignored, always NULL
h	the IO handle to write to
what	what is being written (for error message creation)
source	the data to write
source_size	how many bytes to write

Returns: GNUNET_OK on success, GNUNET_SYSERR otherwise

Definition at line 1135 of file bio.c.

 {
   return GNUNET_BIO_write (h, what, source, source_size);
 }

◆ write_spec_handler_string()

static int write_spec_handler_string	(	void *	cls,
		struct GNUNET_BIO_WriteHandle *	h,
		const char *	what,
		void *	source,
		size_t	source_size
	)

static

Function used internally to write a 0-terminated string from within a write spec.

Parameters

cls	ignored, always NULL
h	the IO handle to write to
what	what is being written (for error message creation)
source	the data to write
source_size	ignored

Returns: GNUNET_OK on success, GNUNET_SYSERR otherwise

Definition at line 1182 of file bio.c.

 {
   const char *s = source;
   return GNUNET_BIO_write_string (h, what, s);
 }

◆ write_spec_handler_int32()

static int write_spec_handler_int32	(	void *	cls,
		struct GNUNET_BIO_WriteHandle *	h,
		const char *	what,
		void *	source,
		size_t	source_size
	)

static

Function used internally to write an (u)int32_t from within a write spec.

Parameters

cls	ignored, always NULL
h	the IO handle to write to
what	what is being written (for error message creation)
source	the data to write
source_size	ignored

Returns: GNUNET_OK on success, GNUNET_SYSERR otherwise

Definition at line 1227 of file bio.c.

 {
   int32_t i = *(int32_t *) source;
   return GNUNET_BIO_write_int32 (h, what, i);
 }

◆ write_spec_handler_int64()

static int write_spec_handler_int64	(	void *	cls,
		struct GNUNET_BIO_WriteHandle *	h,
		const char *	what,
		void *	source,
		size_t	source_size
	)

static

Function used internally to write an (u)int64_t from within a write spec.

Parameters

cls	ignored, always NULL
h	the IO handle to write to
what	what is being written (for error message creation)
source	the data to write
source_size	ignored

Returns: GNUNET_OK on success, GNUNET_SYSERR otherwise

Definition at line 1272 of file bio.c.

 {
   int64_t i = *(int64_t *) source;
   return GNUNET_BIO_write_int64 (h, what, i);
 }

Data Structures

Macros

Enumerations

Functions

Detailed Description

Macro Definition Documentation

◆ LOG

◆ PATH_MAX

◆ BIO_BUFFER_SIZE

Enumeration Type Documentation

◆ IOType

Function Documentation

◆ read_from_file()

◆ read_from_buffer()

◆ write_to_file()

◆ write_to_buffer()

◆ read_spec_handler_object()

◆ read_spec_handler_string()

◆ read_spec_handler_int32()

◆ read_spec_handler_int64()

◆ write_spec_handler_object()

◆ write_spec_handler_string()

◆ write_spec_handler_int32()

◆ write_spec_handler_int64()