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-rw-r--r--libguile/fports.c191
-rw-r--r--libguile/fports.h3
-rw-r--r--libguile/init.c1
3 files changed, 141 insertions, 54 deletions
diff --git a/libguile/fports.c b/libguile/fports.c
index b9a99425f..70732e5a0 100644
--- a/libguile/fports.c
+++ b/libguile/fports.c
@@ -315,65 +315,35 @@ fport_canonicalize_filename (SCM filename)
}
}
+/* scm_open_file_with_encoding
+ Return a new port open on a given file.
-/* scm_open_file
- * Return a new port open on a given file.
- *
- * The mode string must match the pattern: [rwa+]** which
- * is interpreted in the usual unix way.
- *
- * Return the new port.
- */
-SCM_DEFINE (scm_open_file, "open-file", 2, 0, 0,
- (SCM filename, SCM mode),
- "Open the file whose name is @var{filename}, and return a port\n"
- "representing that file. The attributes of the port are\n"
- "determined by the @var{mode} string. The way in which this is\n"
- "interpreted is similar to C stdio. The first character must be\n"
- "one of the following:\n"
- "@table @samp\n"
- "@item r\n"
- "Open an existing file for input.\n"
- "@item w\n"
- "Open a file for output, creating it if it doesn't already exist\n"
- "or removing its contents if it does.\n"
- "@item a\n"
- "Open a file for output, creating it if it doesn't already\n"
- "exist. All writes to the port will go to the end of the file.\n"
- "The \"append mode\" can be turned off while the port is in use\n"
- "@pxref{Ports and File Descriptors, fcntl}\n"
- "@end table\n"
- "The following additional characters can be appended:\n"
- "@table @samp\n"
- "@item b\n"
- "Open the underlying file in binary mode, if supported by the system.\n"
- "Also, open the file using the binary-compatible character encoding\n"
- "\"ISO-8859-1\", ignoring the default port encoding.\n"
- "@item +\n"
- "Open the port for both input and output. E.g., @code{r+}: open\n"
- "an existing file for both input and output.\n"
- "@item 0\n"
- "Create an \"unbuffered\" port. In this case input and output\n"
- "operations are passed directly to the underlying port\n"
- "implementation without additional buffering. This is likely to\n"
- "slow down I/O operations. The buffering mode can be changed\n"
- "while a port is in use @pxref{Ports and File Descriptors,\n"
- "setvbuf}\n"
- "@item l\n"
- "Add line-buffering to the port. The port output buffer will be\n"
- "automatically flushed whenever a newline character is written.\n"
- "@end table\n"
- "In theory we could create read/write ports which were buffered\n"
- "in one direction only. However this isn't included in the\n"
- "current interfaces. If a file cannot be opened with the access\n"
- "requested, @code{open-file} throws an exception.")
-#define FUNC_NAME s_scm_open_file
+ The mode string must match the pattern: [rwa+]** which
+ is interpreted in the usual unix way.
+
+ Unless binary mode is requested, the character encoding of the new
+ port is determined as follows: First, if GUESS_ENCODING is true,
+ 'file-encoding' is used to guess the encoding of the file. If
+ GUESS_ENCODING is false or if 'file-encoding' fails, ENCODING is used
+ unless it is also false. As a last resort, the default port encoding
+ is used. It is an error to pass a non-false GUESS_ENCODING or
+ ENCODING if binary mode is requested.
+
+ Return the new port. */
+SCM
+scm_open_file_with_encoding (SCM filename, SCM mode,
+ SCM guess_encoding, SCM encoding)
+#define FUNC_NAME "open-file"
{
SCM port;
int fdes, flags = 0, binary = 0;
unsigned int retries;
char *file, *md, *ptr;
+ if (SCM_UNLIKELY (!(scm_is_false (encoding) || scm_is_string (encoding))))
+ scm_wrong_type_arg_msg (FUNC_NAME, 0, encoding,
+ "encoding to be string or false");
+
scm_dynwind_begin (0);
file = scm_to_locale_string (filename);
@@ -445,8 +415,43 @@ SCM_DEFINE (scm_open_file, "open-file", 2, 0, 0,
fport_canonicalize_filename (filename));
if (binary)
- /* Use the binary-friendly ISO-8859-1 encoding. */
- scm_i_set_port_encoding_x (port, NULL);
+ {
+ if (scm_is_true (encoding))
+ scm_misc_error (FUNC_NAME,
+ "Encoding specified on a binary port",
+ scm_list_1 (encoding));
+ if (scm_is_true (guess_encoding))
+ scm_misc_error (FUNC_NAME,
+ "Request to guess encoding on a binary port",
+ SCM_EOL);
+
+ /* Use the binary-friendly ISO-8859-1 encoding. */
+ scm_i_set_port_encoding_x (port, NULL);
+ }
+ else
+ {
+ char *enc = NULL;
+
+ if (scm_is_true (guess_encoding))
+ {
+ if (SCM_INPUT_PORT_P (port))
+ enc = scm_i_scan_for_encoding (port);
+ else
+ scm_misc_error (FUNC_NAME,
+ "Request to guess encoding on an output-only port",
+ SCM_EOL);
+ }
+
+ if (!enc && scm_is_true (encoding))
+ {
+ char *buf = scm_to_latin1_string (encoding);
+ enc = scm_gc_strdup (buf, "encoding");
+ free (buf);
+ }
+
+ if (enc)
+ scm_i_set_port_encoding_x (port, enc);
+ }
scm_dynwind_end ();
@@ -454,6 +459,75 @@ SCM_DEFINE (scm_open_file, "open-file", 2, 0, 0,
}
#undef FUNC_NAME
+SCM
+scm_open_file (SCM filename, SCM mode)
+{
+ return scm_open_file_with_encoding (filename, mode, SCM_BOOL_F, SCM_BOOL_F);
+}
+
+/* We can't define these using SCM_KEYWORD, because keywords have not
+ yet been initialized when scm_init_fports is called. */
+static SCM k_guess_encoding = SCM_UNDEFINED;
+static SCM k_encoding = SCM_UNDEFINED;
+
+SCM_DEFINE (scm_i_open_file, "open-file", 2, 0, 1,
+ (SCM filename, SCM mode, SCM keyword_args),
+ "Open the file whose name is @var{filename}, and return a port\n"
+ "representing that file. The attributes of the port are\n"
+ "determined by the @var{mode} string. The way in which this is\n"
+ "interpreted is similar to C stdio. The first character must be\n"
+ "one of the following:\n"
+ "@table @samp\n"
+ "@item r\n"
+ "Open an existing file for input.\n"
+ "@item w\n"
+ "Open a file for output, creating it if it doesn't already exist\n"
+ "or removing its contents if it does.\n"
+ "@item a\n"
+ "Open a file for output, creating it if it doesn't already\n"
+ "exist. All writes to the port will go to the end of the file.\n"
+ "The \"append mode\" can be turned off while the port is in use\n"
+ "@pxref{Ports and File Descriptors, fcntl}\n"
+ "@end table\n"
+ "The following additional characters can be appended:\n"
+ "@table @samp\n"
+ "@item b\n"
+ "Open the underlying file in binary mode, if supported by the system.\n"
+ "Also, open the file using the binary-compatible character encoding\n"
+ "\"ISO-8859-1\", ignoring the default port encoding.\n"
+ "@item +\n"
+ "Open the port for both input and output. E.g., @code{r+}: open\n"
+ "an existing file for both input and output.\n"
+ "@item 0\n"
+ "Create an \"unbuffered\" port. In this case input and output\n"
+ "operations are passed directly to the underlying port\n"
+ "implementation without additional buffering. This is likely to\n"
+ "slow down I/O operations. The buffering mode can be changed\n"
+ "while a port is in use @pxref{Ports and File Descriptors,\n"
+ "setvbuf}\n"
+ "@item l\n"
+ "Add line-buffering to the port. The port output buffer will be\n"
+ "automatically flushed whenever a newline character is written.\n"
+ "@end table\n"
+ "In theory we could create read/write ports which were buffered\n"
+ "in one direction only. However this isn't included in the\n"
+ "current interfaces. If a file cannot be opened with the access\n"
+ "requested, @code{open-file} throws an exception.")
+#define FUNC_NAME s_scm_i_open_file
+{
+ SCM encoding = SCM_BOOL_F;
+ SCM guess_encoding = SCM_BOOL_F;
+
+ scm_c_bind_keyword_arguments (FUNC_NAME, keyword_args, 0,
+ k_guess_encoding, &guess_encoding,
+ k_encoding, &encoding,
+ SCM_UNDEFINED);
+
+ return scm_open_file_with_encoding (filename, mode,
+ guess_encoding, encoding);
+}
+#undef FUNC_NAME
+
/* Building Guile ports from a file descriptor. */
@@ -804,6 +878,15 @@ scm_make_fptob ()
return tc;
}
+/* We can't initialize the keywords from 'scm_init_fports', because
+ keywords haven't yet been initialized at that point. */
+void
+scm_init_fports_keywords ()
+{
+ k_guess_encoding = scm_from_latin1_keyword ("guess-encoding");
+ k_encoding = scm_from_latin1_keyword ("encoding");
+}
+
void
scm_init_fports ()
{
diff --git a/libguile/fports.h b/libguile/fports.h
index cbef0f8ec..c32ed9579 100644
--- a/libguile/fports.h
+++ b/libguile/fports.h
@@ -51,9 +51,12 @@ SCM_API scm_t_bits scm_tc16_fport;
SCM_API SCM scm_setbuf0 (SCM port);
SCM_API SCM scm_setvbuf (SCM port, SCM mode, SCM size);
SCM_API void scm_evict_ports (int fd);
+SCM_API SCM scm_open_file_with_encoding (SCM filename, SCM modes,
+ SCM guess_encoding, SCM encoding);
SCM_API SCM scm_open_file (SCM filename, SCM modes);
SCM_API SCM scm_fdes_to_port (int fdes, char *mode, SCM name);
SCM_API SCM scm_file_port_p (SCM obj);
+SCM_INTERNAL void scm_init_fports_keywords (void);
SCM_INTERNAL void scm_init_fports (void);
/* internal functions */
diff --git a/libguile/init.c b/libguile/init.c
index 57e4902b0..455a772d8 100644
--- a/libguile/init.c
+++ b/libguile/init.c
@@ -444,6 +444,7 @@ scm_i_init_guile (void *base)
scm_init_gettext ();
scm_init_ioext ();
scm_init_keywords (); /* Requires smob_prehistory */
+ scm_init_fports_keywords ();
scm_init_list ();
scm_init_random (); /* Requires smob_prehistory */
scm_init_macros (); /* Requires smob_prehistory and random */