From 5afdca0087dad2994ad4fcdfe7f489f4dbcab7b3 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Wed, 11 Mar 1998 12:42:25 +0000 Subject: LinuxThreads library. 1998-03-11 00:42 Wolfram Gloger * linuxthreads/manager.c: Enable resetting of the thread scheduling policy to SCHED_OTHER when the parent thread has a different one. 1998-02-01 13:51 Ulrich Drepper * sysdeps/unix/sysv/linux/bits/posix_opt.h: Define _POSIX_ASYNCHRONOUS_IO. * sysdeps/pthread/pthread.h: Define bits for Unix98 variants of mutexes. * mutex.c: Implement new mutex types. * internals.h: Include . * libpthread.map: Add __erno_location and __h_errno_location. * errno.c: Return pointer to variable actually in use. This might not be the one in the thread structure. * internals.h (struct _pthread_descr_struct): Add new fields p_errnop and p_h_errnop. * manager.c (__pthread_manager): Set p_errnop and p_h_errnop member of manager thread structure. (pthread_handle_create): Set p_errnop and p_h_errnop members for new thread. * pthread.c: Adapt initializer for thread structures. (__pthread_initial_thread): Set p_errnop and p_h_errnop member. (__pthread_reset_main_thread): Reset p_errnop and p_h_errnop of current thread to global variables. 1998-01-31 17:27 Ulrich Drepper * rwlock.c: New file. * Makefile (libpthread-routines): Add rwlock. * sysdeps/pthread/pthread.h: Define data structures and declare functions. * libpthread.map: Add new functions. 1997-12-18 13:50 Philip Blundell * sysdeps/arm/pt-machine.h: New file; add ARM support. * sysdeps/arm/Implies: likewise. * README: Document it. 1997-12-13 Andreas Schwab * signals.c: Remove unneeded initializer for sigwaited, saving a 1997-04-11 01:18 Andreas Schwab * semaphore.c (sem_init): Set sem_spinlock only if available. 1997-12-04 01:48 Ulrich Drepper * mutex.c: Implement PTHREAD_MUTEX_CHECKERROR. * sysdeps/pthread/pthread.h: Define PTHREAD_MUTEX_CHECKERROR. * Makefile: Update from LinuxThreads 0.7. * internals.h. Likewise. * manager.c: Likewise. * mutex.c: Likewise. * pthread.c: Likewise. * signals.c: Likewise. * specific.c: Likewise. * Examples/ex3.c: Likewise. 1997-11-20 18:13 Ulrich Drepper * pthread.c (__pthread_reset_main_thread): Close pipe only if still open. 1997-10-29 05:38 Ulrich Drepper * wrapsyscall.c: Add socket functions which are also cancelation points. 1997-10-19 21:40 Wolfram Gloger * specific.c (__libc_internal_tsd_set, __libc_internal_tsd_get): New functions for fast thread specific data within libc. * internals.h: Add new array p_libc_specific to struct _pthread_descr_struct. * sysdeps/pthread/bits/libc-lock.h: Declare new functions. 1997-10-13 05:39 Ulrich Drepper * semaphore.h: Add __BEGIN_DECLS/__END_DECLS. Reported by Ralf Corsepius . 1997-08-29 03:05 Ulrich Drepper * internals.h (struct _pthread_descr_struct): Add definitions for two-level specific key handling. * manager.c (pthread_handle_create): Initialize specific memory array. * specific.c: Implement two-level key handling. * weaks.c: Don't provide dummy key handling. * sysdeps/pthread/bits/libc-lock.h: Typedef __libc_lock_t (no #define). Add definition of __libc_key_t. * sysdeps/unix/sysv/linux/bits/local_lim.h: Define PTHREAD_KEYS_MAX as 1024. Add definition of _POSIX_THREAD_DESTRUCTOR_ITERATIONS and PTHREAD_DESTRUCTOR_ITERATIONS. * manager.c (pthread_handle_create): Compare mmap result with MAP_FAILED. * ptfork.c: Rename to __pthread_atfork and make old name a weak alias. * sysdeps/pthread/bits/pthread.h: Add prototype for __pthread_atfork. 1997-08-22 19:04 Richard Henderson sysdeps/sparc -> sysdeps/sparc/sparc32 sysdeps/sparc64 -> sysdeps/sparc/sparc64 * internals.h: Change definition of THREAD_SELF to be an expression, not a statement that did a return. * sysdeps/alpha/pt-machine.h (THREAD_SELF): Update accordingly. * sysdeps/sparc/sparc32/pt-machine.h (THREAD_SELF, INIT_THREAD_SELF): Follow Solaris and use a "system reserved" register (%g6) to hold the thread descriptor. * sysdeps/sparc/sparc64/pt-machine.h: Likewise. 1997-08-03 00:09 Ulrich Drepper * mutex.c: Correct pthread_once. Patch by Xavier Leroy. * sysdeps/pthread/pthread.h: Add prototype for __pthread_once. * sysdeps/pthread/bits/pthread.h: Add macros for __libc_once. * semaphore.c: Include spinlock.h only when needed. * specific.c (__pthread_setsepcific, __pthread_getspecific): Reject keys for entries not in use. * weaks.c: Implement key handling functions for real. 1997-06-29 01:04 Richard Henderson Initial sparc64-linux support: * linuxthreads/sysdeps/sparc64/Implies: New file. * linuxthreads/sysdeps/sparc64/pt-machine.h: Likewise. 1997-06-29 00:48 Ulrich Drepper * semaphore.c: Include spinlock.h at correct place. Patch by HJ Lu. 1997-06-13 10:06 Richard Henderson The Great Bit File Move: * sysdeps/alpha/semaphorebits.h: -> .../bits/semaphore.h. * sysdeps/powerpc/semaphorebits.h: Likewise. * sysdeps/pthread/cmpxchg/semaphorebits.h: Likewise. * sysdeps/pthread/no-cmpxchg/semaphorebits.h: Likewise. * sysdeps/pthread/libc-lock.h: -> bits/ * sysdeps/pthread/stdio-lock.h: Likewise. * sysdeps/unix/sysv/linux/local_lim.h: Likewise. * sysdeps/unix/sysv/linux/posix_opt.h: Likewise. * semaphore.h: Likewise. * sysdeps/pthread/pthread.h: Likewise. * lockfile.c: -> . * semaphore.h: Likewise. * Makefile: (headers): foo.h -> bits/foo.h. * sysdeps/pthread/Makefile: Likewise. 1997-04-11 01:18 Andreas Schwab * semaphore.c (sem_init): Set sem_spinlock only if available. * sysdeps/m68k/pt-machine.h (testandset, __compare_and_swap): Fix asm constraints. 1997-04-09 03:00 Ulrich Drepper Update from LinuxThreads 0.6. * attr.c (pthread_attr_getdetachstate): Use __sched_get_priority_max and __sched_get_priority_min instead of names without `__'. * manager.c: Rewrite large parts to implement opaque pthread_t. * cancel.c: Adapt for opaque pthread_t type. * condvar.c: Likewise. * errno.c: Likewise. * join.c: Likewise. * mutex.c: Likewise. * pthread.c: Likewise. * signals.c: Likewise. * specific.c: Likewise. * restart.h: Likewise. * queue.h: Likewise. * Examples/ex3.c: Likewise. * Examples/ex4.c: Likewise. * sysdeps/pthread/pthread.h: Likewise. * pthread.c: Accumulate time for all threads in thread manager. * semaphore.c: Implement fallback implementation for architectures sometimes missing compare-exchange operations. * cancel.c (pthread_cancel): Validate handle argument. * join.c (pthread_join): Likewise. (pthread_detach): Likewise. * signals.c (pthread_kill): Likewise. * spinlock.h (acquire): Use __sched_yield not sched_yield. * queue.h (enqueue): Enqueue thread according to priority. * internals.c (struct pthread_start_args): New struct for passing args to cloning function. (struct _pthread): Rename to _pthread_descr_struct and adapt for opaque pthread_t. * Examples/Makefile (clean): Pass -f option to rm. * sysdeps/i386/pt-machine.h: Add check for compare-exchange instruction and define TEST_FOR_COMPARE_AND_SWAP. * sysdeps/i386/i486/pt-machine.h: Removed. * sysdeps/unix/sysv/linux/local_lim.h (PTHREAD_THREADS_MAX): Increase to 1024. 1997-04-04 16:38 Ulrich Drepper * restart.h (suspend): Clear p_signal before suspending. (suspend_with_cancellation): Likewise. Patch by Xavier Leroy . * weaks.c: Make __pthread_key_create return 1. * sysdeps/pthread/libc-lock.h: Define __libc_key_create, __libc_getspecific, __libc_setspecific, and __libc_key_t. * sysdeps/pthread/stdio-lock.h: Don't care for implementation not using libio. 1997-03-19 15:13 Miguel de Icaza * sysdeps/sparc/pt-machine (RELEASE): Fix. 1997-03-01 07:55 Geoff Keating * sysdeps/powerpc/Implies: Added. * sysdeps/powerpc/pt-machine.h: Added. * sysdeps/powerpc/semaphorebits.h: Added. 1997-01-22 01:22 Ulrich Drepper * linuxtheads/pthread.c (__pthread_initial_thread): Correct initializer. (__pthread_manager_thread): Likewise. Reported by Andreas Jaeger. 1997-01-18 22:15 Richard Henderson Since sigset_t no longer fits in a register, we can't pass in the thread's initial mask so easily. Take this opportunity to simplify the clone implementation by only accepting a single void* argument. * linuxthreads/manager.c (__pthread_manager): Put thread vitals in the thread struct instead of as arguments through clone. (pthread_start_thread): Look for them there. * linuxthreads/internals.h (struct _pthread): Add p_initial_fn, p_initial_fn_arg, p_initial_mask. Fix __pthread_manager proto. * linuxthreads/pthread.c (pthread_initialize_manager): Revise clone invocation. --- linuxthreads/Examples/Makefile | 15 +++++ linuxthreads/Examples/ex1.c | 36 +++++++++++ linuxthreads/Examples/ex2.c | 116 +++++++++++++++++++++++++++++++++ linuxthreads/Examples/ex3.c | 144 +++++++++++++++++++++++++++++++++++++++++ linuxthreads/Examples/ex4.c | 107 ++++++++++++++++++++++++++++++ linuxthreads/Examples/ex5.c | 102 +++++++++++++++++++++++++++++ 6 files changed, 520 insertions(+) create mode 100644 linuxthreads/Examples/Makefile create mode 100644 linuxthreads/Examples/ex1.c create mode 100644 linuxthreads/Examples/ex2.c create mode 100644 linuxthreads/Examples/ex3.c create mode 100644 linuxthreads/Examples/ex4.c create mode 100644 linuxthreads/Examples/ex5.c (limited to 'linuxthreads/Examples') diff --git a/linuxthreads/Examples/Makefile b/linuxthreads/Examples/Makefile new file mode 100644 index 0000000000..c68b3676a4 --- /dev/null +++ b/linuxthreads/Examples/Makefile @@ -0,0 +1,15 @@ +CC=gcc +CFLAGS=-g -O -Wall -I.. -D_REENTRANT +LIBPTHREAD=../libpthread.a + +PROGS=ex1 ex2 ex3 ex4 ex5 proxy + +all: $(PROGS) + +.c: + $(CC) $(CFLAGS) -o $* $*.c $(LIBPTHREAD) + +$(PROGS): + +clean: + rm -f $(PROGS) diff --git a/linuxthreads/Examples/ex1.c b/linuxthreads/Examples/ex1.c new file mode 100644 index 0000000000..c399fab894 --- /dev/null +++ b/linuxthreads/Examples/ex1.c @@ -0,0 +1,36 @@ +/* Creates two threads, one printing 10000 "a"s, the other printing + 10000 "b"s. + Illustrates: thread creation, thread joining. */ + +#include +#include +#include +#include "pthread.h" + +void * process(void * arg) +{ + int i; + fprintf(stderr, "Starting process %s\n", (char *) arg); + for (i = 0; i < 10000; i++) { + write(1, (char *) arg, 1); + } + return NULL; +} + +int main() +{ + int retcode; + pthread_t th_a, th_b; + void * retval; + + retcode = pthread_create(&th_a, NULL, process, "a"); + if (retcode != 0) fprintf(stderr, "create a failed %d\n", retcode); + retcode = pthread_create(&th_b, NULL, process, "b"); + if (retcode != 0) fprintf(stderr, "create b failed %d\n", retcode); + retcode = pthread_join(th_a, &retval); + if (retcode != 0) fprintf(stderr, "join a failed %d\n", retcode); + retcode = pthread_join(th_b, &retval); + if (retcode != 0) fprintf(stderr, "join b failed %d\n", retcode); + return 0; +} + diff --git a/linuxthreads/Examples/ex2.c b/linuxthreads/Examples/ex2.c new file mode 100644 index 0000000000..3f7f115fda --- /dev/null +++ b/linuxthreads/Examples/ex2.c @@ -0,0 +1,116 @@ +/* The classic producer-consumer example. + Illustrates mutexes and conditions. + All integers between 0 and 9999 should be printed exactly twice, + once to the right of the arrow and once to the left. */ + +#include +#include "pthread.h" + +#define BUFFER_SIZE 16 + +/* Circular buffer of integers. */ + +struct prodcons { + int buffer[BUFFER_SIZE]; /* the actual data */ + pthread_mutex_t lock; /* mutex ensuring exclusive access to buffer */ + int readpos, writepos; /* positions for reading and writing */ + pthread_cond_t notempty; /* signaled when buffer is not empty */ + pthread_cond_t notfull; /* signaled when buffer is not full */ +}; + +/* Initialize a buffer */ + +void init(struct prodcons * b) +{ + pthread_mutex_init(&b->lock, NULL); + pthread_cond_init(&b->notempty, NULL); + pthread_cond_init(&b->notfull, NULL); + b->readpos = 0; + b->writepos = 0; +} + +/* Store an integer in the buffer */ + +void put(struct prodcons * b, int data) +{ + pthread_mutex_lock(&b->lock); + /* Wait until buffer is not full */ + while ((b->writepos + 1) % BUFFER_SIZE == b->readpos) { + pthread_cond_wait(&b->notfull, &b->lock); + /* pthread_cond_wait reacquired b->lock before returning */ + } + /* Write the data and advance write pointer */ + b->buffer[b->writepos] = data; + b->writepos++; + if (b->writepos >= BUFFER_SIZE) b->writepos = 0; + /* Signal that the buffer is now not empty */ + pthread_cond_signal(&b->notempty); + pthread_mutex_unlock(&b->lock); +} + +/* Read and remove an integer from the buffer */ + +int get(struct prodcons * b) +{ + int data; + pthread_mutex_lock(&b->lock); + /* Wait until buffer is not empty */ + while (b->writepos == b->readpos) { + pthread_cond_wait(&b->notempty, &b->lock); + } + /* Read the data and advance read pointer */ + data = b->buffer[b->readpos]; + b->readpos++; + if (b->readpos >= BUFFER_SIZE) b->readpos = 0; + /* Signal that the buffer is now not full */ + pthread_cond_signal(&b->notfull); + pthread_mutex_unlock(&b->lock); + return data; +} + +/* A test program: one thread inserts integers from 1 to 10000, + the other reads them and prints them. */ + +#define OVER (-1) + +struct prodcons buffer; + +void * producer(void * data) +{ + int n; + for (n = 0; n < 10000; n++) { + printf("%d --->\n", n); + put(&buffer, n); + } + put(&buffer, OVER); + return NULL; +} + +void * consumer(void * data) +{ + int d; + while (1) { + d = get(&buffer); + if (d == OVER) break; + printf("---> %d\n", d); + } + return NULL; +} + +int main() +{ + pthread_t th_a, th_b; + void * retval; + + init(&buffer); + /* Create the threads */ + pthread_create(&th_a, NULL, producer, 0); + pthread_create(&th_b, NULL, consumer, 0); + /* Wait until producer and consumer finish. */ + pthread_join(th_a, &retval); + pthread_join(th_b, &retval); + return 0; +} + + + diff --git a/linuxthreads/Examples/ex3.c b/linuxthreads/Examples/ex3.c new file mode 100644 index 0000000000..002bc9042a --- /dev/null +++ b/linuxthreads/Examples/ex3.c @@ -0,0 +1,144 @@ +/* Multi-thread searching. + Illustrates: thread cancellation, cleanup handlers. */ + +#include +#include +#include +#include +#include + +/* Defines the number of searching threads */ +#define NUM_THREADS 5 + +/* Function prototypes */ +void *search(void *); +void print_it(void *); + +/* Global variables */ +pthread_t threads[NUM_THREADS]; +pthread_mutex_t lock; +int tries; + +int main(argc, argv) + int argc; + char ** argv; +{ + int i; + int pid; + + /* create a number to search for */ + pid = getpid(); + printf("Searching for the number = %d...\n", pid); + + /* Initialize the mutex lock */ + pthread_mutex_init(&lock, NULL); + + /* Create the searching threads */ + for (i=0; i +#include +#include +#include +#include + +/* This is a typical example of a library function that uses + static variables to accumulate results between calls. + Here, it just returns the concatenation of all string arguments + that were given to it. */ + +#if 0 + +char * str_accumulate(char * s) +{ + static char accu[1024] = { 0 }; + strcat(accu, s); + return accu; +} + +#endif + +/* Of course, this cannot be used in a multi-threaded program + because all threads store "accu" at the same location. + So, we'll use thread-specific data to have a different "accu" + for each thread. */ + +/* Key identifying the thread-specific data */ +static pthread_key_t str_key; +/* "Once" variable ensuring that the key for str_alloc will be allocated + exactly once. */ +static pthread_once_t str_alloc_key_once = PTHREAD_ONCE_INIT; + +/* Forward functions */ +static void str_alloc_key(void); +static void str_alloc_destroy_accu(void * accu); + +/* Thread-safe version of str_accumulate */ + +char * str_accumulate(char * s) +{ + char * accu; + + /* Make sure the key is allocated */ + pthread_once(&str_alloc_key_once, str_alloc_key); + /* Get the thread-specific data associated with the key */ + accu = (char *) pthread_getspecific(str_key); + /* It's initially NULL, meaning that we must allocate the buffer first. */ + if (accu == NULL) { + accu = malloc(1024); + if (accu == NULL) return NULL; + accu[0] = 0; + /* Store the buffer pointer in the thread-specific data. */ + pthread_setspecific(str_key, (void *) accu); + printf("Thread %lx: allocating buffer at %p\n", pthread_self(), accu); + } + /* Now we can use accu just as in the non thread-safe code. */ + strcat(accu, s); + return accu; +} + +/* Function to allocate the key for str_alloc thread-specific data. */ + +static void str_alloc_key(void) +{ + pthread_key_create(&str_key, str_alloc_destroy_accu); + printf("Thread %lx: allocated key %d\n", pthread_self(), str_key); +} + +/* Function to free the buffer when the thread exits. */ +/* Called only when the thread-specific data is not NULL. */ + +static void str_alloc_destroy_accu(void * accu) +{ + printf("Thread %lx: freeing buffer at %p\n", pthread_self(), accu); + free(accu); +} + +/* Test program */ + +void * process(void * arg) +{ + char * res; + res = str_accumulate("Result of "); + res = str_accumulate((char *) arg); + res = str_accumulate(" thread"); + printf("Thread %lx: \"%s\"\n", pthread_self(), res); + return NULL; +} + +int main(int argc, char ** argv) +{ + char * res; + pthread_t th1, th2; + + res = str_accumulate("Result of "); + pthread_create(&th1, NULL, process, "first"); + pthread_create(&th2, NULL, process, "second"); + res = str_accumulate("initial thread"); + printf("Thread %lx: \"%s\"\n", pthread_self(), res); + pthread_join(th1, NULL); + pthread_join(th2, NULL); + pthread_exit(NULL); +} diff --git a/linuxthreads/Examples/ex5.c b/linuxthreads/Examples/ex5.c new file mode 100644 index 0000000000..366668eb8c --- /dev/null +++ b/linuxthreads/Examples/ex5.c @@ -0,0 +1,102 @@ +/* The classic producer-consumer example, implemented with semaphores. + All integers between 0 and 9999 should be printed exactly twice, + once to the right of the arrow and once to the left. */ + +#include +#include "pthread.h" +#include "semaphore.h" + +#define BUFFER_SIZE 16 + +/* Circular buffer of integers. */ + +struct prodcons { + int buffer[BUFFER_SIZE]; /* the actual data */ + int readpos, writepos; /* positions for reading and writing */ + sem_t sem_read; /* number of elements available for reading */ + sem_t sem_write; /* number of locations available for writing */ +}; + +/* Initialize a buffer */ + +void init(struct prodcons * b) +{ + sem_init(&b->sem_write, 0, BUFFER_SIZE - 1); + sem_init(&b->sem_read, 0, 0); + b->readpos = 0; + b->writepos = 0; +} + +/* Store an integer in the buffer */ + +void put(struct prodcons * b, int data) +{ + /* Wait until buffer is not full */ + sem_wait(&b->sem_write); + /* Write the data and advance write pointer */ + b->buffer[b->writepos] = data; + b->writepos++; + if (b->writepos >= BUFFER_SIZE) b->writepos = 0; + /* Signal that the buffer contains one more element for reading */ + sem_post(&b->sem_read); +} + +/* Read and remove an integer from the buffer */ + +int get(struct prodcons * b) +{ + int data; + /* Wait until buffer is not empty */ + sem_wait(&b->sem_read); + /* Read the data and advance read pointer */ + data = b->buffer[b->readpos]; + b->readpos++; + if (b->readpos >= BUFFER_SIZE) b->readpos = 0; + /* Signal that the buffer has now one more location for writing */ + sem_post(&b->sem_write); + return data; +} + +/* A test program: one thread inserts integers from 1 to 10000, + the other reads them and prints them. */ + +#define OVER (-1) + +struct prodcons buffer; + +void * producer(void * data) +{ + int n; + for (n = 0; n < 10000; n++) { + printf("%d --->\n", n); + put(&buffer, n); + } + put(&buffer, OVER); + return NULL; +} + +void * consumer(void * data) +{ + int d; + while (1) { + d = get(&buffer); + if (d == OVER) break; + printf("---> %d\n", d); + } + return NULL; +} + +int main() +{ + pthread_t th_a, th_b; + void * retval; + + init(&buffer); + /* Create the threads */ + pthread_create(&th_a, NULL, producer, 0); + pthread_create(&th_b, NULL, consumer, 0); + /* Wait until producer and consumer finish. */ + pthread_join(th_a, &retval); + pthread_join(th_b, &retval); + return 0; +} -- cgit 1.4.1