mirror of
https://gitlab.freedesktop.org/cairo/cairo.git
synced 2025-12-24 19:30:10 +01:00
Implement proper cairo-style error-handling for cairo_output_stream_t.
The cairo_output_stream_t object already had an internal status value, but it was annoyingly returning status values from various functions. It also was missing proper shutdown-on-error as well as nil-create semantics. This fixes those shortcomings and adjusts all callers for the new semantics, (leading to simpler and more correct calling code---particularly in the case of cairo-base85-stream.c).
This commit is contained in:
Carl Worth
parent
5a06133eb2
commit
dd67cf6616
6 changed files with 126 additions and 88 deletions
|
|
@ -63,19 +63,13 @@ _expand_four_tuple_to_five (unsigned char four_tuple[4],
|
|||
}
|
||||
}
|
||||
|
||||
static cairo_status_t
|
||||
static void
|
||||
_cairo_base85_wrap_perhaps (cairo_base85_stream_t *stream)
|
||||
{
|
||||
cairo_status_t status;
|
||||
|
||||
if (stream->column >= 72) {
|
||||
status = _cairo_output_stream_write (stream->output, "\n", 1);
|
||||
if (status)
|
||||
return status;
|
||||
_cairo_output_stream_write (stream->output, "\n", 1);
|
||||
stream->column = 0;
|
||||
}
|
||||
|
||||
return CAIRO_STATUS_SUCCESS;
|
||||
}
|
||||
|
||||
static cairo_status_t
|
||||
|
|
@ -83,7 +77,6 @@ _cairo_base85_stream_write_data (void *closure,
|
|||
const unsigned char *data,
|
||||
unsigned int length)
|
||||
{
|
||||
cairo_status_t status;
|
||||
cairo_base85_stream_t *stream = closure;
|
||||
const unsigned char *ptr = data;
|
||||
unsigned char five_tuple[5];
|
||||
|
|
@ -95,49 +88,38 @@ _cairo_base85_stream_write_data (void *closure,
|
|||
if (stream->pending == 4) {
|
||||
_expand_four_tuple_to_five (stream->four_tuple, five_tuple, &is_zero);
|
||||
if (is_zero) {
|
||||
status = _cairo_output_stream_write (stream->output, "z", 1);
|
||||
_cairo_output_stream_write (stream->output, "z", 1);
|
||||
stream->column += 1;
|
||||
} else {
|
||||
status = _cairo_output_stream_write (stream->output, five_tuple, 5);
|
||||
_cairo_output_stream_write (stream->output, five_tuple, 5);
|
||||
stream->column += 5;
|
||||
}
|
||||
if (status)
|
||||
return status;
|
||||
status = _cairo_base85_wrap_perhaps (stream);
|
||||
if (status)
|
||||
return status;
|
||||
_cairo_base85_wrap_perhaps (stream);
|
||||
stream->pending = 0;
|
||||
}
|
||||
}
|
||||
|
||||
return CAIRO_STATUS_SUCCESS;
|
||||
return _cairo_output_stream_get_status (stream->output);
|
||||
}
|
||||
|
||||
static cairo_status_t
|
||||
_cairo_base85_stream_close (void *closure)
|
||||
{
|
||||
cairo_status_t status;
|
||||
cairo_base85_stream_t *stream = closure;
|
||||
unsigned char five_tuple[5];
|
||||
|
||||
if (stream->pending) {
|
||||
memset (stream->four_tuple + stream->pending, 0, 4 - stream->pending);
|
||||
_expand_four_tuple_to_five (stream->four_tuple, five_tuple, NULL);
|
||||
status = _cairo_output_stream_write (stream->output, five_tuple, stream->pending + 1);
|
||||
if (status)
|
||||
return status;
|
||||
_cairo_output_stream_write (stream->output, five_tuple, stream->pending + 1);
|
||||
stream->column += stream->pending + 1;
|
||||
status = _cairo_base85_wrap_perhaps (stream);
|
||||
if (status)
|
||||
return status;
|
||||
_cairo_base85_wrap_perhaps (stream);
|
||||
}
|
||||
|
||||
/* Mark end of base85 data */
|
||||
status = _cairo_output_stream_printf (stream->output, "~>\n");
|
||||
if (status)
|
||||
return status;
|
||||
_cairo_output_stream_printf (stream->output, "~>\n");
|
||||
|
||||
return CAIRO_STATUS_SUCCESS;
|
||||
return _cairo_output_stream_get_status (stream->output);
|
||||
}
|
||||
|
||||
cairo_output_stream_t *
|
||||
|
|
@ -147,7 +129,7 @@ _cairo_base85_stream_create (cairo_output_stream_t *output)
|
|||
|
||||
stream = malloc (sizeof (cairo_base85_stream_t));
|
||||
if (stream == NULL)
|
||||
return NULL;
|
||||
return (cairo_output_stream_t *) &cairo_output_stream_nil;
|
||||
|
||||
stream->output = output;
|
||||
stream->pending = 0;
|
||||
|
|
|
|||
|
|
@ -49,6 +49,25 @@ struct _cairo_output_stream {
|
|||
void *closure;
|
||||
unsigned long position;
|
||||
cairo_status_t status;
|
||||
cairo_bool_t closed;
|
||||
};
|
||||
|
||||
const cairo_output_stream_t cairo_output_stream_nil = {
|
||||
NULL, /* write_data */
|
||||
NULL, /* close_func */
|
||||
NULL, /* closure */
|
||||
0, /* position */
|
||||
CAIRO_STATUS_NO_MEMORY,
|
||||
FALSE /* closed */
|
||||
};
|
||||
|
||||
static const cairo_output_stream_t cairo_output_stream_nil_write_error = {
|
||||
NULL, /* write_data */
|
||||
NULL, /* close_func */
|
||||
NULL, /* closure */
|
||||
0, /* position */
|
||||
CAIRO_STATUS_WRITE_ERROR,
|
||||
FALSE /* closed */
|
||||
};
|
||||
|
||||
cairo_output_stream_t *
|
||||
|
|
@ -60,41 +79,54 @@ _cairo_output_stream_create (cairo_write_func_t write_data,
|
|||
|
||||
stream = malloc (sizeof (cairo_output_stream_t));
|
||||
if (stream == NULL)
|
||||
return NULL;
|
||||
return (cairo_output_stream_t *) &cairo_output_stream_nil;
|
||||
|
||||
stream->write_data = write_data;
|
||||
stream->close_func = close_func;
|
||||
stream->closure = closure;
|
||||
stream->position = 0;
|
||||
stream->status = CAIRO_STATUS_SUCCESS;
|
||||
stream->closed = FALSE;
|
||||
|
||||
return stream;
|
||||
}
|
||||
|
||||
cairo_status_t
|
||||
_cairo_output_stream_destroy (cairo_output_stream_t *stream)
|
||||
void
|
||||
_cairo_output_stream_close (cairo_output_stream_t *stream)
|
||||
{
|
||||
cairo_status_t status = CAIRO_STATUS_SUCCESS;
|
||||
cairo_status_t status;
|
||||
|
||||
if (stream->close_func)
|
||||
if (stream->closed)
|
||||
return;
|
||||
|
||||
if (stream->close_func) {
|
||||
status = stream->close_func (stream->closure);
|
||||
if (status)
|
||||
stream->status = status;
|
||||
}
|
||||
|
||||
free (stream);
|
||||
|
||||
return status;
|
||||
stream->closed = TRUE;
|
||||
}
|
||||
|
||||
cairo_status_t
|
||||
void
|
||||
_cairo_output_stream_destroy (cairo_output_stream_t *stream)
|
||||
{
|
||||
_cairo_output_stream_close (stream);
|
||||
free (stream);
|
||||
}
|
||||
|
||||
void
|
||||
_cairo_output_stream_write (cairo_output_stream_t *stream,
|
||||
const void *data, size_t length)
|
||||
{
|
||||
if (length == 0)
|
||||
return CAIRO_STATUS_SUCCESS;
|
||||
return;
|
||||
|
||||
if (stream->status)
|
||||
return;
|
||||
|
||||
stream->status = stream->write_data (stream->closure, data, length);
|
||||
stream->position += length;
|
||||
|
||||
return stream->status;
|
||||
}
|
||||
|
||||
void
|
||||
|
|
@ -106,6 +138,9 @@ _cairo_output_stream_write_hex_string (cairo_output_stream_t *stream,
|
|||
char buffer[2];
|
||||
int i, column;
|
||||
|
||||
if (stream->status)
|
||||
return;
|
||||
|
||||
for (i = 0, column = 0; i < length; i++, column++) {
|
||||
if (column == 38) {
|
||||
_cairo_output_stream_write (stream, "\n", 1);
|
||||
|
|
@ -178,8 +213,7 @@ enum {
|
|||
* formatting. This functionality is only for internal use and we
|
||||
* only implement the formats we actually use.
|
||||
*/
|
||||
|
||||
cairo_status_t
|
||||
void
|
||||
_cairo_output_stream_vprintf (cairo_output_stream_t *stream,
|
||||
const char *fmt, va_list ap)
|
||||
{
|
||||
|
|
@ -188,6 +222,9 @@ _cairo_output_stream_vprintf (cairo_output_stream_t *stream,
|
|||
const char *f;
|
||||
int length_modifier;
|
||||
|
||||
if (stream->status)
|
||||
return;
|
||||
|
||||
f = fmt;
|
||||
p = buffer;
|
||||
while (*f != '\0') {
|
||||
|
|
@ -250,24 +287,19 @@ _cairo_output_stream_vprintf (cairo_output_stream_t *stream,
|
|||
}
|
||||
|
||||
_cairo_output_stream_write (stream, buffer, p - buffer);
|
||||
|
||||
return stream->status;
|
||||
}
|
||||
|
||||
cairo_status_t
|
||||
void
|
||||
_cairo_output_stream_printf (cairo_output_stream_t *stream,
|
||||
const char *fmt, ...)
|
||||
{
|
||||
va_list ap;
|
||||
cairo_status_t status;
|
||||
|
||||
va_start (ap, fmt);
|
||||
|
||||
status = _cairo_output_stream_vprintf (stream, fmt, ap);
|
||||
_cairo_output_stream_vprintf (stream, fmt, ap);
|
||||
|
||||
va_end (ap);
|
||||
|
||||
return status;
|
||||
}
|
||||
|
||||
long
|
||||
|
|
@ -312,16 +344,10 @@ cairo_output_stream_t *
|
|||
_cairo_output_stream_create_for_file (const char *filename)
|
||||
{
|
||||
FILE *file;
|
||||
cairo_output_stream_t *stream;
|
||||
|
||||
file = fopen (filename, "wb");
|
||||
if (file == NULL)
|
||||
return NULL;
|
||||
return (cairo_output_stream_t *) &cairo_output_stream_nil_write_error;
|
||||
|
||||
stream = _cairo_output_stream_create (stdio_write, stdio_close, file);
|
||||
|
||||
if (stream == NULL)
|
||||
fclose (file);
|
||||
|
||||
return stream;
|
||||
return _cairo_output_stream_create (stdio_write, stdio_close, file);
|
||||
}
|
||||
|
|
|
|||
|
|
@ -333,11 +333,13 @@ cairo_pdf_surface_create_for_stream (cairo_write_func_t write,
|
|||
double width_in_points,
|
||||
double height_in_points)
|
||||
{
|
||||
cairo_status_t status;
|
||||
cairo_output_stream_t *stream;
|
||||
|
||||
stream = _cairo_output_stream_create (write, NULL, closure);
|
||||
if (stream == NULL) {
|
||||
_cairo_error (CAIRO_STATUS_NO_MEMORY);
|
||||
status = _cairo_output_stream_get_status (stream);
|
||||
if (status) {
|
||||
_cairo_error (status);
|
||||
return (cairo_surface_t*) &_cairo_surface_nil;
|
||||
}
|
||||
|
||||
|
|
@ -368,11 +370,13 @@ cairo_pdf_surface_create (const char *filename,
|
|||
double width_in_points,
|
||||
double height_in_points)
|
||||
{
|
||||
cairo_status_t status;
|
||||
cairo_output_stream_t *stream;
|
||||
|
||||
stream = _cairo_output_stream_create_for_file (filename);
|
||||
if (stream == NULL) {
|
||||
_cairo_error (CAIRO_STATUS_NO_MEMORY);
|
||||
status = _cairo_output_stream_get_status (stream);
|
||||
if (status) {
|
||||
_cairo_error (status);
|
||||
return (cairo_surface_t*) &_cairo_surface_nil;
|
||||
}
|
||||
|
||||
|
|
|
|||
|
|
@ -178,11 +178,13 @@ cairo_ps_surface_create (const char *filename,
|
|||
double width_in_points,
|
||||
double height_in_points)
|
||||
{
|
||||
cairo_status_t status;
|
||||
cairo_output_stream_t *stream;
|
||||
|
||||
stream = _cairo_output_stream_create_for_file (filename);
|
||||
if (stream == NULL) {
|
||||
_cairo_error (CAIRO_STATUS_NO_MEMORY);
|
||||
status = _cairo_output_stream_get_status (stream);
|
||||
if (status) {
|
||||
_cairo_error (status);
|
||||
return (cairo_surface_t*) &_cairo_surface_nil;
|
||||
}
|
||||
|
||||
|
|
@ -216,11 +218,13 @@ cairo_ps_surface_create_for_stream (cairo_write_func_t write_func,
|
|||
double width_in_points,
|
||||
double height_in_points)
|
||||
{
|
||||
cairo_status_t status;
|
||||
cairo_output_stream_t *stream;
|
||||
|
||||
stream = _cairo_output_stream_create (write_func, NULL, closure);
|
||||
if (stream == NULL) {
|
||||
_cairo_error (CAIRO_STATUS_NO_MEMORY);
|
||||
status = _cairo_output_stream_get_status (stream);
|
||||
if (status) {
|
||||
_cairo_error (status);
|
||||
return (cairo_surface_t*) &_cairo_surface_nil;
|
||||
}
|
||||
|
||||
|
|
@ -758,18 +762,13 @@ emit_image (cairo_ps_surface_t *surface,
|
|||
|
||||
/* Compressed image data (Base85 encoded) */
|
||||
base85_stream = _cairo_base85_stream_create (surface->stream);
|
||||
if (base85_stream == NULL) {
|
||||
status = CAIRO_STATUS_NO_MEMORY;
|
||||
goto bail3;
|
||||
}
|
||||
|
||||
status = _cairo_output_stream_write (base85_stream, compressed, compressed_size);
|
||||
if (status) {
|
||||
_cairo_output_stream_destroy (base85_stream);
|
||||
goto bail3;
|
||||
}
|
||||
_cairo_output_stream_write (base85_stream, compressed, compressed_size);
|
||||
_cairo_output_stream_close (base85_stream);
|
||||
|
||||
status = _cairo_output_stream_destroy (base85_stream);
|
||||
status = _cairo_output_stream_get_status (base85_stream);
|
||||
|
||||
_cairo_output_stream_destroy (base85_stream);
|
||||
|
||||
bail3:
|
||||
free (compressed);
|
||||
|
|
|
|||
|
|
@ -143,11 +143,15 @@ cairo_svg_surface_create_for_stream (cairo_write_func_t write,
|
|||
double width,
|
||||
double height)
|
||||
{
|
||||
cairo_status_t status;
|
||||
cairo_output_stream_t *stream;
|
||||
|
||||
stream = _cairo_output_stream_create (write, NULL, closure);
|
||||
if (stream == NULL)
|
||||
return NULL;
|
||||
status = _cairo_output_stream_get_status (stream);
|
||||
if (status) {
|
||||
_cairo_error (status);
|
||||
return (cairo_surface_t *) &cairo_surface_nil;
|
||||
}
|
||||
|
||||
return _cairo_svg_surface_create_for_stream_internal (stream, width, height);
|
||||
}
|
||||
|
|
@ -157,11 +161,15 @@ cairo_svg_surface_create (const char *filename,
|
|||
double width,
|
||||
double height)
|
||||
{
|
||||
cairo_status_t status;
|
||||
cairo_output_stream_t *stream;
|
||||
|
||||
stream = _cairo_output_stream_create_for_file (filename);
|
||||
if (stream == NULL)
|
||||
return NULL;
|
||||
status = _cairo_output_stream_get_status (stream);
|
||||
if (status) {
|
||||
_cairo_error (status);
|
||||
return (cairo_surface_t *) &cairo_surface_nil;
|
||||
}
|
||||
|
||||
return _cairo_svg_surface_create_for_stream_internal (stream, width, height);
|
||||
}
|
||||
|
|
|
|||
|
|
@ -2124,6 +2124,8 @@ _cairo_utf8_to_utf16 (const unsigned char *str,
|
|||
|
||||
typedef struct _cairo_output_stream cairo_output_stream_t;
|
||||
|
||||
extern const cairo_private cairo_output_stream_t cairo_output_stream_nil;
|
||||
|
||||
/* We already have the following declared in cairo.h:
|
||||
|
||||
typedef cairo_status_t (*cairo_write_func_t) (void *closure,
|
||||
|
|
@ -2132,18 +2134,27 @@ typedef cairo_status_t (*cairo_write_func_t) (void *closure,
|
|||
*/
|
||||
typedef cairo_status_t (*cairo_close_func_t) (void *closure);
|
||||
|
||||
|
||||
/* This function never returns NULL. If an error occurs (NO_MEMORY)
|
||||
* while trying to create the output stream this function returns a
|
||||
* valid pointer to a nil output stream.
|
||||
*
|
||||
* Note that even with a nil surface, the close_func callback will be
|
||||
* called by a call to _cairo_output_stream_close or
|
||||
* _cairo_output_stream_destroy.
|
||||
*/
|
||||
cairo_private cairo_output_stream_t *
|
||||
_cairo_output_stream_create (cairo_write_func_t write_func,
|
||||
cairo_close_func_t close_func,
|
||||
void *closure);
|
||||
|
||||
/* Most cairo destroy functions don't return a status, but we do here
|
||||
* to allow the return status from the close_func callback to be
|
||||
* captured. */
|
||||
cairo_private cairo_status_t
|
||||
cairo_private void
|
||||
_cairo_output_stream_close (cairo_output_stream_t *stream);
|
||||
|
||||
cairo_private void
|
||||
_cairo_output_stream_destroy (cairo_output_stream_t *stream);
|
||||
|
||||
cairo_private cairo_status_t
|
||||
cairo_private void
|
||||
_cairo_output_stream_write (cairo_output_stream_t *stream,
|
||||
const void *data, size_t length);
|
||||
|
||||
|
|
@ -2152,14 +2163,14 @@ _cairo_output_stream_write_hex_string (cairo_output_stream_t *stream,
|
|||
const char *data,
|
||||
size_t length);
|
||||
|
||||
unsigned char *
|
||||
cairo_private unsigned char *
|
||||
_cairo_lzw_compress (unsigned char *data, unsigned long *data_size_in_out);
|
||||
|
||||
cairo_private cairo_status_t
|
||||
cairo_private void
|
||||
_cairo_output_stream_vprintf (cairo_output_stream_t *stream,
|
||||
const char *fmt, va_list ap);
|
||||
|
||||
cairo_private cairo_status_t
|
||||
cairo_private void
|
||||
_cairo_output_stream_printf (cairo_output_stream_t *stream,
|
||||
const char *fmt, ...) CAIRO_PRINTF_FORMAT(2, 3);
|
||||
|
||||
|
|
@ -2169,6 +2180,14 @@ _cairo_output_stream_get_position (cairo_output_stream_t *status);
|
|||
cairo_private cairo_status_t
|
||||
_cairo_output_stream_get_status (cairo_output_stream_t *stream);
|
||||
|
||||
/* This function never returns NULL. If an error occurs (NO_MEMORY or
|
||||
* WRITE_ERROR) while trying to create the output stream this function
|
||||
* returns a valid pointer to a nil output stream.
|
||||
*
|
||||
* NOTE: Even if a nil surface is returned, the caller should still
|
||||
* call _cairo_output_stream_destroy (or _cairo_output_stream_close at
|
||||
* least) in order to ensure that everything is properly cleaned up.
|
||||
*/
|
||||
cairo_private cairo_output_stream_t *
|
||||
_cairo_output_stream_create_for_file (const char *filename);
|
||||
|
||||
|
|
|
|||
Loading…
Add table
Reference in a new issue