| 1 | First of all: C89 or better. If you don't have that, port gcc first. |
| 2 | |
| 3 | Use of C language extensions throughout the X server tree |
| 4 | --------------------------------------------------------- |
| 5 | |
| 6 | Optional extensions: |
| 7 | The server will still build if your toolchain does not support these |
| 8 | extensions, although the results may not be optimal. |
| 9 | |
| 10 | * _X_SENTINEL(x): member x of the passed structure must be NULL, e.g.: |
| 11 | void parseOptions(Option *options _X_SENTINEL(0)); |
| 12 | parseOptions("foo", "bar", NULL); /* this is OK */ |
| 13 | parseOptions("foo", "bar", "baz"); /* this is not */ |
| 14 | This definition comes from Xfuncproto.h in the core |
| 15 | protocol headers. |
| 16 | * _X_ATTRIBUTE_PRINTF(x, y): This function has printf-like semantics; |
| 17 | check the format string when built with |
| 18 | -Wformat (gcc) or similar. |
| 19 | * _X_EXPORT: this function should appear in symbol tables. |
| 20 | * _X_HIDDEN: this function should not appear in the _dynamic_ symbol |
| 21 | table. |
| 22 | * _X_INTERNAL: like _X_HIDDEN, but attempt to ensure that this function |
| 23 | is never called from another module. |
| 24 | * _X_INLINE: inline this functon if possible (generally obeyed unless |
| 25 | disabling optimisations). |
| 26 | * _X_DEPRECATED: warn on use of this function. |
| 27 | |
| 28 | Mandatory extensions: |
| 29 | The server will not build if your toolchain does not support these extensions. |
| 30 | |
| 31 | * named initialisers: explicitly initialising structure members, e.g.: |
| 32 | struct foo bar = { .baz = quux, .brian = "dog" }; |
| 33 | * variadic macros: macros with a variable number of arguments, e.g.: |
| 34 | #define DebugF(x, ...) /**/ |
| 35 | * interleaved code and declarations: { foo = TRUE; int bar; do_stuff(); } |
| 36 | |
| 37 | |
| 38 | Use of library facilities throughout the X server tree |
| 39 | ------------------------------------------------------------- |
| 40 | |
| 41 | Non-OS-dependent code can assume facilities at least as good as |
| 42 | the non-OS-facility parts of POSIX-1.2001. Ideally this would |
| 43 | be C99, but even gcc+glibc doesn't implement that yet. |
| 44 | |
| 45 | Unix-like systems are assumed to be at least as good as UNIX03. |
| 46 | |
| 47 | Note that there are two Windows ports, Cygwin and MinGW: |
| 48 | - Cygwin is more or less like Linux. |
| 49 | - MinGW is more restrictive. Windows does not provide the required |
| 50 | POSIX facilities, so some non-OS-dependent code is stubbed out or |
| 51 | has an alternate implementation if WIN32 is defined. Code that |
| 52 | needs to be portable to Windows should be careful to, well, be portable. |
| 53 | |
| 54 | |
| 55 | Required OS facilities |
| 56 | ------------------------------------------------------------- |
| 57 | |
| 58 | Linux systems must be at least 2.4 or later. As a practical matter |
| 59 | though, 2.4 kernels never receive any testing. Use 2.6 already. |
| 60 | |
| 61 | TODO: Solaris. |
| 62 | |
| 63 | TODO: *BSD. |
| 64 | |
| 65 | Windows-dependent code assumes at least NT 5.1. |
| 66 | |
| 67 | OSX support is generally limited to the most recent version. Currently |
| 68 | that means 10.5. |