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Diffstat (limited to 'linuxthreads/internals.h')
| -rw-r--r-- | linuxthreads/internals.h | 280 |
1 files changed, 280 insertions, 0 deletions
diff --git a/linuxthreads/internals.h b/linuxthreads/internals.h new file mode 100644 index 0000000..7939605 --- /dev/null +++ b/linuxthreads/internals.h @@ -0,0 +1,280 @@ +/* Linuxthreads - a simple clone()-based implementation of Posix */ +/* threads for Linux. */ +/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */ +/* */ +/* This program is free software; you can redistribute it and/or */ +/* modify it under the terms of the GNU Library General Public License */ +/* as published by the Free Software Foundation; either version 2 */ +/* of the License, or (at your option) any later version. */ +/* */ +/* This program is distributed in the hope that it will be useful, */ +/* but WITHOUT ANY WARRANTY; without even the implied warranty of */ +/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the */ +/* GNU Library General Public License for more details. */ + +/* Internal data structures */ + +/* Includes */ + +#include <bits/libc-lock.h> /* for _LIBC_TSD_KEY_N */ +#include <setjmp.h> +#include <signal.h> +#include <unistd.h> +#include <sys/types.h> + +#include "pt-machine.h" + +/* Arguments passed to thread creation routine */ + +struct pthread_start_args { + void * (*start_routine)(void *); /* function to run */ + void * arg; /* its argument */ + sigset_t mask; /* initial signal mask for thread */ + int schedpolicy; /* initial scheduling policy (if any) */ + struct sched_param schedparam; /* initial scheduling parameters (if any) */ +}; + + +/* We keep thread specific data in a special data structure, a two-level + array. The top-level array contains pointers to dynamically allocated + arrays of a certain number of data pointers. So we can implement a + sparse array. Each dynamic second-level array has + PTHREAD_KEY_2NDLEVEL_SIZE + entries. This value shouldn't be too large. */ +#define PTHREAD_KEY_2NDLEVEL_SIZE 32 + +/* We need to address PTHREAD_KEYS_MAX key with PTHREAD_KEY_2NDLEVEL_SIZE + keys in each subarray. */ +#define PTHREAD_KEY_1STLEVEL_SIZE \ + ((PTHREAD_KEYS_MAX + PTHREAD_KEY_2NDLEVEL_SIZE - 1) \ + / PTHREAD_KEY_2NDLEVEL_SIZE) + + +#define PTHREAD_START_ARGS_INITIALIZER { NULL, NULL, {{0, }}, 0, { 0 } } + +/* The type of thread descriptors */ + +typedef struct _pthread_descr_struct * pthread_descr; + +struct _pthread_descr_struct { + pthread_descr p_nextlive, p_prevlive; + /* Double chaining of active threads */ + pthread_descr p_nextwaiting; /* Next element in the queue holding the thr */ + pthread_t p_tid; /* Thread identifier */ + int p_pid; /* PID of Unix process */ + int p_priority; /* Thread priority (== 0 if not realtime) */ + int * p_spinlock; /* Spinlock for synchronized accesses */ + int p_signal; /* last signal received */ + sigjmp_buf * p_signal_jmp; /* where to siglongjmp on a signal or NULL */ + sigjmp_buf * p_cancel_jmp; /* where to siglongjmp on a cancel or NULL */ + char p_terminated; /* true if terminated e.g. by pthread_exit */ + char p_detached; /* true if detached */ + char p_exited; /* true if the assoc. process terminated */ + void * p_retval; /* placeholder for return value */ + int p_retcode; /* placeholder for return code */ + pthread_descr p_joining; /* thread joining on that thread or NULL */ + struct _pthread_cleanup_buffer * p_cleanup; /* cleanup functions */ + char p_cancelstate; /* cancellation state */ + char p_canceltype; /* cancellation type (deferred/async) */ + char p_canceled; /* cancellation request pending */ + int * p_errnop; /* pointer to used errno variable */ + int p_errno; /* error returned by last system call */ + int * p_h_errnop; /* pointer to used h_errno variable */ + int p_h_errno; /* error returned by last netdb function */ + struct pthread_start_args p_start_args; /* arguments for thread creation */ + void ** p_specific[PTHREAD_KEY_1STLEVEL_SIZE]; /* thread-specific data */ + void * p_libc_specific[_LIBC_TSD_KEY_N]; /* thread-specific data for libc */ +}; + +/* The type of thread handles. */ + +typedef struct pthread_handle_struct * pthread_handle; + +struct pthread_handle_struct { + int h_spinlock; /* Spinlock for sychronized access */ + pthread_descr h_descr; /* Thread descriptor or NULL if invalid */ +}; + +/* The type of messages sent to the thread manager thread */ + +struct pthread_request { + pthread_descr req_thread; /* Thread doing the request */ + enum { /* Request kind */ + REQ_CREATE, REQ_FREE, REQ_PROCESS_EXIT, REQ_MAIN_THREAD_EXIT + } req_kind; + union { /* Arguments for request */ + struct { /* For REQ_CREATE: */ + const pthread_attr_t * attr; /* thread attributes */ + void * (*fn)(void *); /* start function */ + void * arg; /* argument to start function */ + sigset_t mask; /* signal mask */ + } create; + struct { /* For REQ_FREE: */ + pthread_descr thread; /* descriptor of thread to free */ + } free; + struct { /* For REQ_PROCESS_EXIT: */ + int code; /* exit status */ + } exit; + } req_args; +}; + + +/* Signals used for suspend/restart and for cancellation notification. */ + +#ifdef SIGRTMIN +/* The have real-time signals. */ +extern int __pthread_sig_restart; +extern int __pthread_sig_cancel; +# define PTHREAD_SIG_RESTART __pthread_sig_restart +# define PTHREAD_SIG_CANCEL __pthread_sig_cancel +#else +# define PTHREAD_SIG_RESTART SIGUSR1 +# define PTHREAD_SIG_CANCEL SIGUSR2 +#endif + +/* Global array of thread handles, used for validating a thread id + and retrieving the corresponding thread descriptor. Also used for + mapping the available stack segments. */ + +extern struct pthread_handle_struct __pthread_handles[PTHREAD_THREADS_MAX]; + +/* Descriptor of the initial thread */ + +extern struct _pthread_descr_struct __pthread_initial_thread; + +/* Descriptor of the manager thread */ + +extern struct _pthread_descr_struct __pthread_manager_thread; + +/* Descriptor of the main thread */ + +extern pthread_descr __pthread_main_thread; + +/* Limit between the stack of the initial thread (above) and the + stacks of other threads (below). Aligned on a STACK_SIZE boundary. + Initially 0, meaning that the current thread is (by definition) + the initial thread. */ + +extern char *__pthread_initial_thread_bos; + +/* File descriptor for sending requests to the thread manager. + Initially -1, meaning that pthread_initialize must be called. */ + +extern int __pthread_manager_request; + +/* Other end of the pipe for sending requests to the thread manager. */ + +extern int __pthread_manager_reader; + +/* Limits of the thread manager stack. */ + +extern char *__pthread_manager_thread_bos; +extern char *__pthread_manager_thread_tos; + +/* Pending request for a process-wide exit */ + +extern int __pthread_exit_requested, __pthread_exit_code; + +/* Return the handle corresponding to a thread id */ + +static inline pthread_handle thread_handle(pthread_t id) +{ + return &__pthread_handles[id % PTHREAD_THREADS_MAX]; +} + +/* Validate a thread handle. Must have acquired h->h_spinlock before. */ + +static inline int invalid_handle(pthread_handle h, pthread_t id) +{ + return h->h_descr == NULL || h->h_descr->p_tid != id; +} + +/* Fill in defaults left unspecified by pt-machine.h. */ + +/* The page size we can get from the system. This should likely not be + changed by the machine file but, you never know. */ +#ifndef PAGE_SIZE +#define PAGE_SIZE (sysconf (_SC_PAGE_SIZE)) +#endif + +/* The max size of the thread stack segments. If the default + THREAD_SELF implementation is used, this must be a power of two and + a multiple of PAGE_SIZE. */ +#ifndef STACK_SIZE +#define STACK_SIZE (2 * 1024 * 1024) +#endif + +/* The initial size of the thread stack. Must be a multiple of PAGE_SIZE. */ +#ifndef INITIAL_STACK_SIZE +#define INITIAL_STACK_SIZE (4 * PAGE_SIZE) +#endif + +/* Size of the thread manager stack. The "- 32" avoids wasting space + with some malloc() implementations. */ +#ifndef THREAD_MANAGER_STACK_SIZE +#define THREAD_MANAGER_STACK_SIZE (2 * PAGE_SIZE - 32) +#endif + +/* The base of the "array" of thread stacks. The array will grow down from + here. Defaults to the calculated bottom of the initial application + stack. */ +#ifndef THREAD_STACK_START_ADDRESS +#define THREAD_STACK_START_ADDRESS __pthread_initial_thread_bos +#endif + +/* Get some notion of the current stack. Need not be exactly the top + of the stack, just something somewhere in the current frame. */ +#ifndef CURRENT_STACK_FRAME +#define CURRENT_STACK_FRAME ({ char __csf; &__csf; }) +#endif + +/* Recover thread descriptor for the current thread */ + +static inline pthread_descr thread_self (void) __attribute__ ((const)); +static inline pthread_descr thread_self (void) +{ +#ifdef THREAD_SELF + return THREAD_SELF; +#else + char *sp = CURRENT_STACK_FRAME; + if (sp >= __pthread_initial_thread_bos) + return &__pthread_initial_thread; + else if (sp >= __pthread_manager_thread_bos + && sp < __pthread_manager_thread_tos) + return &__pthread_manager_thread; + else + return (pthread_descr)(((unsigned long)sp | (STACK_SIZE-1))+1) - 1; +#endif +} + +/* Debugging */ + +#ifdef DEBUG +#include <assert.h> +#define ASSERT assert +#define MSG __pthread_message +#else +#define ASSERT(x) +#define MSG(msg,arg...) +#endif + +/* Internal global functions */ + +void __pthread_destroy_specifics(void); +void __pthread_perform_cleanup(void); +void __pthread_sighandler(int sig); +void __pthread_message(char * fmt, long arg, ...); +int __pthread_manager(void *reqfd); +void __pthread_manager_sighandler(int sig); +void __pthread_reset_main_thread(void); +void __fresetlockfiles(void); + + +/* Prototypes for the function without cancelation support when the + normal version has it. */ +extern int __libc_close (int fd); +extern int __libc_nanosleep (const struct timespec *requested_time, + struct timespec *remaining); +extern int __libc_read (int fd, void *buf, size_t count); +extern pid_t __libc_waitpid (pid_t pid, int *stat_loc, int options); +extern int __libc_write (int fd, const void *buf, size_t count); |