From 5d2dea82b6af09843c8fb6db696ad18586006a5a Mon Sep 17 00:00:00 2001
From: Christopher Lang <christopher.lang.256@gmail.com>
Date: Sun, 29 Sep 2024 23:02:15 +0100
Subject: [PATCH] Add NOTHREADS macro for vacuous pthread symbols

---
 common/pthreads_cross.c | 22 ++++++++++++++++++++++
 common/pthreads_cross.h | 22 ++++++++++++++++++++++
 common/workerpool.c     |  3 +++
 3 files changed, 47 insertions(+)

diff --git a/common/pthreads_cross.c b/common/pthreads_cross.c
index 04e556cf..a5eaed25 100644
--- a/common/pthreads_cross.c
+++ b/common/pthreads_cross.c
@@ -248,9 +248,31 @@ unsigned int pcthread_get_num_procs()
 
 #else
 
+#ifdef NOTHREADS
+int pthread_create(pthread_t *thread, pthread_attr_t *attr, void *(*start_routine)(void *), void *arg) { return 0; }
+int pthread_join(pthread_t thread, void **value_ptr) { return 0; }
+int pthread_detach(pthread_t thread) { return 0; }
+
+int pthread_mutex_init(pthread_mutex_t *mutex, pthread_mutexattr_t *attr) { return 0; }
+int pthread_mutex_destroy(pthread_mutex_t *mutex) { return 0; }
+int pthread_mutex_lock(pthread_mutex_t *mutex) { return 0; }
+int pthread_mutex_unlock(pthread_mutex_t *mutex) { return 0; }
+
+int pthread_cond_init(pthread_cond_t *cond, pthread_condattr_t *attr) { return 0; }
+int pthread_cond_destroy(pthread_cond_t *cond) { return 0; }
+int pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex) { return 0; }
+int pthread_cond_timedwait(pthread_cond_t *cond, pthread_mutex_t *mutex, const struct timespec *abstime) { return 0; }
+int pthread_cond_signal(pthread_cond_t *cond) { return 0; }
+int pthread_cond_broadcast(pthread_cond_t *cond) { return 0; }
+
+int sched_yield(void) { return 0; }
+unsigned int pcthread_get_num_procs() { return 1; }
+#else
 #include <unistd.h>
 unsigned int pcthread_get_num_procs()
 {
     return (unsigned int)sysconf(_SC_NPROCESSORS_ONLN);
 }
 #endif
+
+#endif
diff --git a/common/pthreads_cross.h b/common/pthreads_cross.h
index fc40c9ba..d0b77baf 100644
--- a/common/pthreads_cross.h
+++ b/common/pthreads_cross.h
@@ -23,6 +23,7 @@ SOFTWARE.
 #ifndef __CPTHREAD_H__
 #define __CPTHREAD_H__
 
+#ifndef NOTHREADS
 #ifdef _WIN32
 #include <stdbool.h>
 #include <windows.h>
@@ -30,6 +31,8 @@ SOFTWARE.
 #include <pthread.h>
 #include <sched.h>
 #endif
+#endif
+
 #include <time.h>
 
 #ifdef _WIN32
@@ -67,6 +70,25 @@ int sched_yield(void);
 #endif
 #endif
 
+#ifdef NOTHREADS
+int pthread_create(pthread_t *thread, pthread_attr_t *attr, void *(*start_routine)(void *), void *arg);
+int pthread_join(pthread_t thread, void **value_ptr);
+int pthread_detach(pthread_t thread);
+
+int pthread_mutex_init(pthread_mutex_t *mutex, pthread_mutexattr_t *attr);
+int pthread_mutex_destroy(pthread_mutex_t *mutex);
+int pthread_mutex_lock(pthread_mutex_t *mutex);
+int pthread_mutex_unlock(pthread_mutex_t *mutex);
+
+int pthread_cond_init(pthread_cond_t *cond, pthread_condattr_t *attr);
+int pthread_cond_destroy(pthread_cond_t *cond);
+int pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex);
+int pthread_cond_timedwait(pthread_cond_t *cond, pthread_mutex_t *mutex, const struct timespec *abstime);
+int pthread_cond_signal(pthread_cond_t *cond);
+int pthread_cond_broadcast(pthread_cond_t *cond);
+
+int sched_yield(void);
+#endif
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/common/workerpool.c b/common/workerpool.c
index 6b73541c..c5721d8f 100644
--- a/common/workerpool.c
+++ b/common/workerpool.c
@@ -96,6 +96,9 @@ void *worker_thread(void *p)
 workerpool_t *workerpool_create(int nthreads)
 {
     assert(nthreads > 0);
+#ifdef NOTHREADS
+    nthreads = 1;
+#endif
 
     workerpool_t *wp = calloc(1, sizeof(workerpool_t));
     wp->nthreads = nthreads;