On Sat, Dec 29, 2018 at 12:33:24PM -1000, Joey Pabalinas wrote: > On Sat, Dec 29, 2018 at 07:02:18PM +0100, Willy Tarreau wrote: > > + * - the lower level is the arch-specific syscall() definition, > > consisting in > > + * assembly code in compound expressions. These are called > > my_syscall0() to > > + * my_syscall6() depending on the number of arguments. The MIPS > > + * implementation is limited to 5 arguments. All input arguments are > > cast > > + * to a long stored in a register. These expressions always return the > > + * syscall's return value as a signed long value which is often either > > a > > + * pointer or the negated errno value. > > + * > > + * - the second level is mostly architecture-independent. It is made of > > + * static functions called sys_<name>() which rely on my_syscallN() > > + * depending on the syscall definition. These functions are responsible > > + * for exposing the appropriate types for the syscall arguments (int, > > + * pointers, etc) and for setting the appropriate return type (often > > int). > > + * A few of them are architecture-specific because the syscalls are > > not all > > + * mapped exactly the same among architectures. For example, some > > archs do > > + * not implement select() and need pselect6() instead, so the > > sys_select() > > + * function will have to abstract this. > > + * > > + * - the third level is the libc call definition. It exposes the lower > > raw > > + * sys_<name>() calls in a way that looks like what a libc usually > > does, > > + * takes care of specific input values, and of setting errno upon > > error. > > + * There can be minor variations compared to standard libc calls. For > > + * example the open() call always takes 3 args here. > > Shouldn't these sentences begin with a capitalized "The" for > consistency?
Not sure since they're just list items. But probably as such they should end with a semi-colon and not a dot. Anyway, this is minor and likely for a later update to the file. > > /* some archs (at least aarch64) don't expose the regular syscalls anymore > > by > > * default, either because they have an "_at" replacement, or because > > there are > > * more modern alternatives. For now we'd rather still use them. > > Also here. Shouldn't this begin with a capitalized "Some"? Definitely! Same, I won't emit a patch just for this, Paul already queued it. Thanks! Willy
