Start implementing proper error handling.

[cdecl99.git] / doc / man / libcdecl.3

diff --git a/doc/man/libcdecl.3 b/doc/man/libcdecl.3
index 97fc41a568bf19c99bcc9f11078e67030c470366..489d7a9ef7eb8fce9a409c70d1aab18735e2efdd 100644 (file)
--- a/doc/man/libcdecl.3
+++ b/doc/man/libcdecl.3
@@ -14,6 +14,8 @@
 .Fd size_t cdecl_explain(char *buf, size_t n, struct cdecl *decl);
 .Fd size_t cdecl_declare(char *buf, size_t n, struct cdecl *decl);
 .Pp
 .Fd size_t cdecl_explain(char *buf, size_t n, struct cdecl *decl);
 .Fd size_t cdecl_declare(char *buf, size_t n, struct cdecl *decl);
 .Pp

+.Fd const struct cdecl_error *cdecl_get_error(void);
+.Pp

 .Fd int cdecl_spec_kind(struct cdecl_declspec *spec);
 .Sh DESCRIPTION
 .Nm
 .Fd int cdecl_spec_kind(struct cdecl_declspec *spec);
 .Sh DESCRIPTION
 .Nm


@@ -28,6 +30,31 @@ manual page.
 is intended to be portable to any system with a working C implementation that
 at least makes an effort to support C99.  The library is thread-safe when
 appropriate facilities exist and are enabled at build time.
 is intended to be portable to any system with a working C implementation that
 at least makes an effort to support C99.  The library is thread-safe when
 appropriate facilities exist and are enabled at build time.

+.Sh NAMESPACE
+.Nm
+reserves all identifiers beginning with either
+.Li cdecl_
+or
+.Li CDECL_
+in both the tag and ordinary identifier namespaces.  All external names
+beginning with
+.Li cdecl_
+are reserved, and the library headers may define object-like macros beginning
+with
+.Li CDECL_ .
+The
+.Nm
+library headers may use other identifiers where they do not pollute the global
+namespaces, such as struct members or function parameter names.  Such internal
+identifiers shall not contain any upper-case letters.  As these internal
+identifiers can only conflict with object-like macros, this practice is safe as
+long as the convention of defining object-like macros using upper-case letters
+is adhered to.
+.Pp
+External names beginning with
+.Li cdecl
+followed by two consecutive underscores are not considered part of the ABI and
+are thus subject to change at any time.

 .Sh ABSTRACT SYNTAX TREE
 The functions in
 .Nm
 .Sh ABSTRACT SYNTAX TREE
 The functions in
 .Nm


@@ -219,6 +246,44 @@ each function parameter has exactly one full declarator (abstract or
 otherwise).   If
 .Va variadic
 is true, then the function is variadic.
 otherwise).   If
 .Va variadic
 is true, then the function is variadic.

+.Sh ERROR HANDLING
+Some functions in
+.Nm
+can fail.  Such functions will be documented as indicating an error condition
+in a particular way.  It is sometimes necessary to know more about a particular
+error in order to print an informative error message or perform some other
+action.  To facilitate this,
+.Nm
+provides a structure which describes a particular error.
+.Bd -literal -offset indent
+struct cdecl_error {
+       unsigned code;
+       const char *str;
+};
+.Ed
+.Pp
+The
+.Va code
+member identifies the sort of error which has occurred, while the
+.Va str
+member points to a string containing a human-readable description of the error.
+This error information can be retrieved by calling the function
+.Pp
+.Fd const struct cdecl_error *cdecl_get_error(void);
+.Pp
+which returns a pointer to the error structure most recently generated in the
+current thread.  It is therefore thread-safe in that errors occurring in
+another thread will not interfere with the current one.  The returned pointer
+shall remain valid until the next call to any function from
+.Nm
+by the same thread, except that multiple consecutive calls to
+.Va cdecl_get_error
+shall all return the same value.  The same applies to the
+.Va str
+pointer inside the error structure itself.
+.Pp
+If this function is called before an error has been indicated by an earlier
+call in the same thread, the behaviour is undefined.

 .Sh PARSING DECLARATIONS
 To parse a declaration, the function
 .Pp
 .Sh PARSING DECLARATIONS
 To parse a declaration, the function
 .Pp