CtplInputStream

CtplInputStream — CTPL's data input stream

Synopsis

#include <ctpl/ctpl.h>

#define             CTPL_EOF
                    CtplInputStream;
CtplInputStream *   ctpl_input_stream_new               (GInputStream *stream,
                                                         const gchar *name);
CtplInputStream *   ctpl_input_stream_new_for_gfile     (GFile *file,
                                                         GError **error);
CtplInputStream *   ctpl_input_stream_new_for_memory    (const gchar *data,
                                                         gssize length,
                                                         GDestroyNotify destroy,
                                                         const gchar *name);
CtplInputStream *   ctpl_input_stream_new_for_path      (const gchar *path,
                                                         GError **error);
CtplInputStream *   ctpl_input_stream_new_for_uri       (const gchar *uri,
                                                         GError **error);
CtplInputStream *   ctpl_input_stream_ref               (CtplInputStream *stream);
void                ctpl_input_stream_unref             (CtplInputStream *stream);
GInputStream *      ctpl_input_stream_get_stream        (const CtplInputStream *stream);
const gchar *       ctpl_input_stream_get_name          (const CtplInputStream *stream);
guint               ctpl_input_stream_get_line          (const CtplInputStream *stream);
guint               ctpl_input_stream_get_line_position (const CtplInputStream *stream);
void                ctpl_input_stream_set_error         (CtplInputStream *stream,
                                                         GError **error,
                                                         GQuark domain,
                                                         gint code,
                                                         const gchar *format,
                                                         ...);
gssize              ctpl_input_stream_read              (CtplInputStream *stream,
                                                         void *buffer,
                                                         gsize count,
                                                         GError **error);
gchar               ctpl_input_stream_get_c             (CtplInputStream *stream,
                                                         GError **error);
gdouble             ctpl_input_stream_read_float        (CtplInputStream *stream,
                                                         GError **error);
glong               ctpl_input_stream_read_int          (CtplInputStream *stream,
                                                         GError **error);
gboolean            ctpl_input_stream_read_number       (CtplInputStream *stream,
                                                         CtplValue *value,
                                                         GError **error);
gchar *             ctpl_input_stream_read_string_literal
                                                        (CtplInputStream *stream,
                                                         GError **error);
#define             ctpl_input_stream_read_symbol       (stream,
                                                         error)
gchar *             ctpl_input_stream_read_symbol_full  (CtplInputStream *stream,
                                                         gssize max_len,
                                                         gsize *length,
                                                         GError **error);
gchar *             ctpl_input_stream_read_word         (CtplInputStream *stream,
                                                         const gchar *accept,
                                                         gssize accept_len,
                                                         gssize max_len,
                                                         gsize *length,
                                                         GError **error);
gssize              ctpl_input_stream_peek              (CtplInputStream *stream,
                                                         void *buffer,
                                                         gsize count,
                                                         GError **error);
gchar               ctpl_input_stream_peek_c            (CtplInputStream *stream,
                                                         GError **error);
#define             ctpl_input_stream_peek_symbol       (stream,
                                                         max_len,
                                                         error)
gchar *             ctpl_input_stream_peek_symbol_full  (CtplInputStream *stream,
                                                         gssize max_len,
                                                         gsize *length,
                                                         GError **error);
gchar *             ctpl_input_stream_peek_word         (CtplInputStream *stream,
                                                         const gchar *accept,
                                                         gssize accept_len,
                                                         gssize max_len,
                                                         gsize *length,
                                                         GError **error);
gssize              ctpl_input_stream_skip              (CtplInputStream *stream,
                                                         gsize count,
                                                         GError **error);
gssize              ctpl_input_stream_skip_blank        (CtplInputStream *stream,
                                                         GError **error);
gssize              ctpl_input_stream_skip_word         (CtplInputStream *stream,
                                                         const gchar *reject,
                                                         gssize reject_len,
                                                         GError **error);
gboolean            ctpl_input_stream_eof               (CtplInputStream *stream,
                                                         GError **error);
gboolean            ctpl_input_stream_eof_fast          (CtplInputStream *stream);

Description

The data input stream used by CTPL. This is a buffered input stream on top of GInputStream with current position information (line and position) and some read scheme facilities (words (ctpl_input_stream_read_word()), string literals (ctpl_input_stream_read_string_literal()), ...).

A CtplInputStream is created with ctpl_input_stream_new(). There is some convenient wrappers to create it from in-memory data (ctpl_input_stream_new_for_memory()), GFiles (ctpl_input_stream_new_for_gfile()), path (ctpl_input_stream_new_for_path()) and URIs (ctpl_input_stream_new_for_uri()). CtplInputStream object uses a GObject-like refcounting, via ctpl_input_stream_ref() and ctpl_input_stream_unref().

The errors that the functions in this module can throw comes from the G_IO_ERROR or CTPL_IO_ERROR domains unless otherwise mentioned.

Details

CTPL_EOF

#define CTPL_EOF  0

End-Of-File constant.

Since 0.2


CtplInputStream

typedef struct _CtplInputStream CtplInputStream;

An opaque object representing an input data stream.


ctpl_input_stream_new ()

CtplInputStream *   ctpl_input_stream_new               (GInputStream *stream,
                                                         const gchar *name);

Creates a new CtplInputStream for a GInputStream. This function adds a reference to the GInputStream.

stream :

A GInputStream

name :

The name of the stream, or NULL for none. This is used to identify the stream in error messages

Returns :

A new CtplInputStream

Since 0.2


ctpl_input_stream_new_for_gfile ()

CtplInputStream *   ctpl_input_stream_new_for_gfile     (GFile *file,
                                                         GError **error);

Creates a new CtplInputStream for a GFile. This is a wrapper around g_file_read() that also sets the name of the stream to the file's name. The errors this function can throw are those from the G_IO_ERROR domain. See ctpl_input_stream_new().

file :

A GFile to read

error :

Return location for errors, or NULL to ignore them

Returns :

A new CtplInputStream on success, NULL on error.

Since 0.2


ctpl_input_stream_new_for_memory ()

CtplInputStream *   ctpl_input_stream_new_for_memory    (const gchar *data,
                                                         gssize length,
                                                         GDestroyNotify destroy,
                                                         const gchar *name);

Creates a new CtplInputStream for in-memory data. This is a wrapper around GMemoryInputStream; see ctpl_input_stream_new().

data :

Data for which create the stream

length :

length of data

destroy :

GDestroyNotify to call on data when finished, or NULL

name :

The name of the stream to identify it in error messages

Returns :

A new CtplInputStream for the given data

Since 0.2


ctpl_input_stream_new_for_path ()

CtplInputStream *   ctpl_input_stream_new_for_path      (const gchar *path,
                                                         GError **error);

Creates a new CtplInputStream for a path. This is a wrapper for ctpl_input_stream_new_for_gfile() that simply creates a GFile for the given path and call ctpl_input_stream_new_for_gfile() on it.

path :

A local or absolute path to pass to g_file_new_for_path()

error :

Return location for errors, or NULL to ignore them

Returns :

A new CtplInputStream on success, NULL on error.

Since 0.2


ctpl_input_stream_new_for_uri ()

CtplInputStream *   ctpl_input_stream_new_for_uri       (const gchar *uri,
                                                         GError **error);

Creates a new CtplInputStream for an URI. This is a wrapper for ctpl_input_stream_new_for_gfile() that simply creates a GFile for the given URI and call ctpl_input_stream_new_for_gfile() on it.

uri :

A URI to pass to g_file_new_for_uri().

error :

Return location for errors, or NULL to ignore them

Returns :

A new CtplInputStream on success, NULL on error.

Since 0.2


ctpl_input_stream_ref ()

CtplInputStream *   ctpl_input_stream_ref               (CtplInputStream *stream);

Adds a reference to a CtplInputStream.

stream :

A CtplInputStream

Returns :

The stream

Since 0.2


ctpl_input_stream_unref ()

void                ctpl_input_stream_unref             (CtplInputStream *stream);

Removes a reference from a CtplInputStream. If the reference count drops to 0, frees the stream.

stream :

A CtplInputStream

Since 0.2


ctpl_input_stream_get_stream ()

GInputStream *      ctpl_input_stream_get_stream        (const CtplInputStream *stream);

Gets the underlying GInputStream associated with a CtplInputStream.

stream :

A CtplInputStream

Returns :

The underlying GInputStream of stream. [transfer none]

Since 0.3


ctpl_input_stream_get_name ()

const gchar *       ctpl_input_stream_get_name          (const CtplInputStream *stream);

Gets the name associated with a CtplInputStream.

stream :

A CtplInputStream

Returns :

The name associated with stream, or NULL if none. [allow-none]

Since 0.3


ctpl_input_stream_get_line ()

guint               ctpl_input_stream_get_line          (const CtplInputStream *stream);

Gets the current line number of a CtplInputStream.

stream :

A CtplInputStream

Returns :

The current line number associated with stream.

Since 0.3


ctpl_input_stream_get_line_position ()

guint               ctpl_input_stream_get_line_position (const CtplInputStream *stream);

Gets the current offset position in the current line, in bytes, in a CtplInputStream.

stream :

A CtplInputStream

Returns :

The current offset in the current line.

Since 0.3


ctpl_input_stream_set_error ()

void                ctpl_input_stream_set_error         (CtplInputStream *stream,
                                                         GError **error,
                                                         GQuark domain,
                                                         gint code,
                                                         const gchar *format,
                                                         ...);

This is a wrapper around g_set_error() that adds stream's position information to the reported error.

stream :

A CtplInputStream

error :

A GError to fill, may be NULL. [out callee-allocates][allow-none callee-allocates]

domain :

The domain of the error to report

code :

The code of the error

format :

printf-like format string

... :

printf-like arguments for format

Since 0.2


ctpl_input_stream_read ()

gssize              ctpl_input_stream_read              (CtplInputStream *stream,
                                                         void *buffer,
                                                         gsize count,
                                                         GError **error);

Reads data from a CtplInputStream.

stream :

A CtplInputStream

buffer :

buffer to fill with the read data

count :

number of bytes to read (must be less than or qual to G_MAXSSIZE, or a G_IO_ERROR_INVALID_ARGUMENT will be thrown)

error :

return location for errors, or NULL to ignore them

Returns :

The number of bytes read, or -1 on error.

Since 0.2


ctpl_input_stream_get_c ()

gchar               ctpl_input_stream_get_c             (CtplInputStream *stream,
                                                         GError **error);

Reads a character from a CtplInputStream.

stream :

A CtplInputStream

error :

Return location for errors, or NULL to ignore them

Returns :

The read character, or CTPL_EOF at stream's end or on error

Since


ctpl_input_stream_read_float ()

gdouble             ctpl_input_stream_read_float        (CtplInputStream *stream,
                                                         GError **error);

Reads a real form a CtplInputStream. See ctpl_input_stream_read_number() for details.

stream :

A CtplInputStream

error :

Return location for errors, or NULL to ignore them

Returns :

The read value, or 0 on error.

Since 0.2


ctpl_input_stream_read_int ()

glong               ctpl_input_stream_read_int          (CtplInputStream *stream,
                                                         GError **error);

Reads an integer from a CtplInputStream. See ctpl_input_stream_read_number() for details.

stream :

A CtplInputStream

error :

Return location for errors, or NULL to ignore them

Returns :

The read integer, or 0 on error.

Since 0.2


ctpl_input_stream_read_number ()

gboolean            ctpl_input_stream_read_number       (CtplInputStream *stream,
                                                         CtplValue *value,
                                                         GError **error);

Reads a number from a CtplInputStream. A number can be a plain decimal integer, a binary integer prefixed with 0b, an octal integer prefixed with 0o, a hexadecimal integer prefixed with 0x, a decimal real with possible decimal exponent separated by a e or a hexadecimal real with possible decimal power separated by a p; each possibly preceded by a plus or minus sign. The decimal point of real numbers is always a period (.).

Example 15. Some numeric constants

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/* Decimal integers */
42
+512
/* Binary integers */
0b11
/* Octal integers */
0o755
/* Hexadecimal integers */
-0x7FFBE
0x8ff
/* Decimal reals */
+2.1
1.024e3
/* Hexadecimal reals */
0x71F.A0
-0x88fe.2p8


stream :

A CtplInputStream

value :

A CtplValue to fill with the read number, either CTPL_VTYPE_INT or CTPL_VTYPE_FLOAT

error :

Return location for errors, or NULL to ignore them

Returns :

TRUE on success, FALSE otherwise.

Since 0.2


ctpl_input_stream_read_string_literal ()

gchar *             ctpl_input_stream_read_string_literal
                                                        (CtplInputStream *stream,
                                                         GError **error);

Reads a string quoted with " (double quote), containing possible escaping sequences escaped by \ (backslash). A plain escaping character (backslash) need to be escaped too, otherwise it will simply escape the next character.

For instance, a string might look like this:

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"a valid string with \"special\" characters such as \\ (backslash) and \" (double quotes)"

stream :

A CtplInputStream

error :

Return location for errors, or NULL to ignore them

Returns :

The read string, or NULL on error

Since 0.2


ctpl_input_stream_read_symbol()

#define             ctpl_input_stream_read_symbol(stream, error)

Reads a symbol (a word composed of the characters from CTPL_SYMBOL_CHARS). See ctpl_input_stream_read_word() and ctpl_input_stream_read_symbol_full().

stream :

A CtplInputStream

error :

return location for errors, or NULL to ignore them

Returns :

A newly allocated string containing the read symbol, or NULL on error.

Since 0.2


ctpl_input_stream_read_symbol_full ()

gchar *             ctpl_input_stream_read_symbol_full  (CtplInputStream *stream,
                                                         gssize max_len,
                                                         gsize *length,
                                                         GError **error);

Reads a symbol from a CtplInputStream. A symbol is a word composed of the characters from CTPL_SYMBOL_CHARS. See ctpl_input_stream_read_word() and ctpl_input_stream_read_symbol().

stream :

A CtplInputStream

max_len :

The maximum number of bytes to read, or -1 for no limit. [default -1]

length :

Return location for the read symbol length, or NULL. [out][allow-none]

error :

return location for errors, or NULL to ignore them

Returns :

A newly allocated string containing the read symbol, or NULL on error.

Since 0.2


ctpl_input_stream_read_word ()

gchar *             ctpl_input_stream_read_word         (CtplInputStream *stream,
                                                         const gchar *accept,
                                                         gssize accept_len,
                                                         gssize max_len,
                                                         gsize *length,
                                                         GError **error);

Reads a word from a CtplInputStream. A word is a sequence of characters referenced by accept. Note that the word might be empty if no characters matching accept are found before one that doesn't match.

For example, reading a word composed of any ASCII lowercase characters may be as the following:

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gchar  *word;
GError *error = NULL;

word = ctpl_input_stream_read_word (stream, "abcdefghijklmnopqrstuvwxyz", -1,
                                    -1, NULL, &error);
if (! word) {
  /* deal with the error */
} else {
  printf ("Read the word \"%s\"\n", word);
  g_free (word);
}

stream :

A CtplInputStream

accept :

string of the character acceptable for the word

accept_len :

length of accept, can be -1 if accept is 0-terminated

max_len :

maximum number of bytes to read, or -1 for no limit. [default -1]

length :

return location for the length of the read word, or NULL. [out][allow-none]

error :

Return location for errors, or NULL to ignore them

Returns :

A newly allocated string containing the read word that should be freed with g_free() when no longer needed; or NULL on error.

Since 0.2


ctpl_input_stream_peek ()

gssize              ctpl_input_stream_peek              (CtplInputStream *stream,
                                                         void *buffer,
                                                         gsize count,
                                                         GError **error);

Peeks data from a CtplInputStream. Peeking data is like reading, but it doesn't removes the data from the stream.

Warning

A peek might resize the internal stream's cache to fit at least count. Therefore, peeking too much data at once should be done with some care.

stream :

A CtplInputStream

buffer :

buffer to fill with the peeked data

count :

number of bytes to peek (must be less than or qual to G_MAXSSIZE, or a G_IO_ERROR_INVALID_ARGUMENT will be thrown)

error :

return location for errors, or NULL to ignore them

Returns :

the number of bytes peeked, or -1 on error

Since 0.2


ctpl_input_stream_peek_c ()

gchar               ctpl_input_stream_peek_c            (CtplInputStream *stream,
                                                         GError **error);

Peeks a character from a CtplInputStream. This may be implemented as a macro.

stream :

A CtplInputStream

error :

Return location for errors, or NULL to ignore them

Returns :

The peeked character, or CTPL_EOF at end of the stream or on error

Since 0.2


ctpl_input_stream_peek_symbol()

#define             ctpl_input_stream_peek_symbol(stream, max_len, error)

Peeks a symbol from a CtplInputStream. See ctpl_input_stream_peek_word() and ctpl_input_stream_peek_symbol_full().

stream :

A CtplInputStream

max_len :

The maximum number of bytes to peek, even if they still matches, or -1 for no limit. [default -1]

error :

Return location for errors, or NULL to ignore them

Returns :

A newly allocated string containing the peeked symbol, or NULL on error.

Since 0.2


ctpl_input_stream_peek_symbol_full ()

gchar *             ctpl_input_stream_peek_symbol_full  (CtplInputStream *stream,
                                                         gssize max_len,
                                                         gsize *length,
                                                         GError **error);

Peeks a symbol from a CtplInputStream. See ctpl_input_stream_peek_word() and ctpl_input_stream_peek_symbol().

stream :

A CtplInputStream

max_len :

The maximum number of bytes to peek, even if they still matches, or -1 for no limit. [default -1]

length :

Return location for the peeked length, or NULL. [out][allow-none]

error :

Return location for errors, or NULL to ignore them

Returns :

A newly allocated string containing the peeked symbol, or NULL on error.

Since 0.2


ctpl_input_stream_peek_word ()

gchar *             ctpl_input_stream_peek_word         (CtplInputStream *stream,
                                                         const gchar *accept,
                                                         gssize accept_len,
                                                         gssize max_len,
                                                         gsize *length,
                                                         GError **error);

Peeks a word from a CtplInputStream. See ctpl_input_stream_peek() and ctpl_input_stream_read_word().

stream :

A CtplInputStream

accept :

string of the character acceptable for the word

accept_len :

length of accept, can be -1 if accept is 0-terminated

max_len :

maximum number of bytes to peek, or -1 for no limit. [default -1]

length :

return location for the length of the read word, or NULL. [out][allow-none]

error :

return location for errors, or NULL to ignore them

Returns :

A newly allocated string containing the peeked word that should be freed with g_free() when no longer needed; or NULL on error.

Since 0.2


ctpl_input_stream_skip ()

gssize              ctpl_input_stream_skip              (CtplInputStream *stream,
                                                         gsize count,
                                                         GError **error);

Skips count bytes from a CtplInputStream.

stream :

A CtplInputStream

count :

Number of bytes to skip

error :

Return location for errors, or NULL to ignore them

Returns :

The number of skipped bytes, or -1 on error.

Since


ctpl_input_stream_skip_blank ()

gssize              ctpl_input_stream_skip_blank        (CtplInputStream *stream,
                                                         GError **error);

Skips blank characters (as reported by ctpl_is_blank()). See ctpl_input_stream_skip().

stream :

A CtplInputStream

error :

Return location for errors, or NULL to ignore them

Returns :

The number of skipped characters.

Since 0.2


ctpl_input_stream_skip_word ()

gssize              ctpl_input_stream_skip_word         (CtplInputStream *stream,
                                                         const gchar *reject,
                                                         gssize reject_len,
                                                         GError **error);

Skips all the characters matching reject from a CtplInputStream until the first that doesn't match.

stream :

A CtplInputStream

reject :

A string of the characters to skip

reject_len :

Length of reject, can be -1 if 0-terminated

error :

Return location for errors, or NULL to ignore them

Returns :

The number of skipped bytes, or -1 on error.

Since 0.2


ctpl_input_stream_eof ()

gboolean            ctpl_input_stream_eof               (CtplInputStream *stream,
                                                         GError **error);

Reliably checks if the stream reached its end. The error this function can throw are from the G_IO_ERROR domain.

Warning

The return value of this function is quite uncommon: it returns TRUE if at stream's end, but also on error. This is to be more convenient since this function is mainly used to ensure the stream does NOT have reached its end. To differentiate an error from EOF, check if the error was set.

stream :

A CtplInputStream

error :

return location for errors, or NULL to ignore them

Returns :

FALSE if not at EOF, TRUE otherwise (note that this includes I/O error).

Since 0.2


ctpl_input_stream_eof_fast ()

gboolean            ctpl_input_stream_eof_fast          (CtplInputStream *stream);

Checks if a CtplInputStream reached its end. See also ctpl_input_stream_eof().

Warning

This function is reliable only to know if the stream already reached EOF, not if next read will do so. To reliably check whether the stream have data to be read, first call a function that will do a read if necessary, and then reach the end of the stream. For example, use ctpl_input_stream_peek_c():

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ctpl_input_stream_peek_c (stream, &error);
/* deal with the possible error */
if (ctpl_input_stream_eof_fast (stream)) {
  /* here EOF is reliable */
}

There is also a reliable version, but that can fail: ctpl_input_stream_eof().

stream :

A CtplInputStream

Returns :

TRUE if at end of stream, FALSE otherwise.