termux-packages/packages/notcurses/pthread_cancel.patch

--- a/src/demo/input.c
+++ b/src/demo/input.c
@@ -4,6 +4,15 @@
 #include <pthread.h>
 #include "demo.h"
 
+#ifdef __ANDROID__
+#define PTHREAD_CANCELED ((void *)-1)
+static void
+thread_signal_handler(int signum)
+{
+  pthread_exit(PTHREAD_CANCELED);
+}
+#endif
+
 typedef struct nciqueue {
   ncinput ni;
   struct nciqueue *next;
@@ -118,6 +127,15 @@
 
 static void *
 ultramegaok_demo(void* vnc){
+#ifdef __ANDROID__
+  struct sigaction actions;
+  memset(&actions, 0, sizeof(actions));
+  sigemptyset(&actions.sa_mask);
+  actions.sa_flags = 0;
+  actions.sa_handler = thread_signal_handler;
+  sigaction(SIGUSR2, &actions, NULL);
+#endif
+
   ncinput ni;
   struct notcurses* nc = vnc;
   uint32_t id;
@@ -176,7 +194,11 @@
 int stop_input(void){
   int ret = 0;
   if(input_pipefds[0] >= 0){
+#ifndef __ANDROID__
     ret |= pthread_cancel(tid);
+#else
+    ret |= pthread_kill(tid, SIGUSR2);
+#endif
     ret |= pthread_join(tid, NULL);
     ret |= close(input_pipefds[0]);
     ret |= close(input_pipefds[1]);
--- a/src/demo/reel.c
+++ b/src/demo/reel.c
@@ -7,6 +7,15 @@
 #include <pthread.h>
 #include "demo.h"
 
+#ifdef __ANDROID__
+#define PTHREAD_CANCELED ((void *)-1)
+static void
+thread_signal_handler(int signum)
+{
+  pthread_exit(PTHREAD_CANCELED);
+}
+#endif
+
 #define INITIAL_TABLET_COUNT 4
 
 static pthread_mutex_t renderlock = PTHREAD_MUTEX_INITIALIZER;
@@ -27,9 +36,13 @@
 kill_tablet(tabletctx** tctx){
   tabletctx* t = *tctx;
   if(t){
+#ifndef __ANDROID__
     if(pthread_cancel(t->tid)){
       fprintf(stderr, "Warning: error sending pthread_cancel (%s)\n", strerror(errno));
     }
+#else
+    pthread_kill(t->tid, SIGUSR2);
+#endif
     if(pthread_join(t->tid, NULL)){
       fprintf(stderr, "Warning: error joining pthread (%s)\n", strerror(errno));
     }
@@ -117,6 +130,15 @@
 // events for its tablet.
 static void*
 tablet_thread(void* vtabletctx){
+#ifdef __ANDROID__
+  struct sigaction actions;
+  memset(&actions, 0, sizeof(actions));
+  sigemptyset(&actions.sa_mask);
+  actions.sa_flags = 0;
+  actions.sa_handler = thread_signal_handler;
+  sigaction(SIGUSR2, &actions, NULL);
+#endif
+
   static int MINSECONDS = 0;
   tabletctx* tctx = vtabletctx;
   while(true){
--- a/src/demo/outro.c
+++ b/src/demo/outro.c
@@ -1,6 +1,10 @@
 #include <pthread.h>
 #include "demo.h"
 
+#ifdef __ANDROID__
+#define PTHREAD_CANCELED ((void *)-1)
+#endif
+
 static int y;
 static int targy;
 static unsigned xstart;
--- a/src/lib/fd.c
+++ b/src/lib/fd.c
@@ -23,6 +23,15 @@
 #define NCPOLLEVENTS (POLLIN)
 #endif
 
+#ifdef __ANDROID__
+#define PTHREAD_CANCELED ((void *)-1)
+static void
+thread_signal_handler(int signum)
+{
+  pthread_exit(PTHREAD_CANCELED);
+}
+#endif
+
 // release the memory and fd, but don't join the thread (since we might be
 // getting called within the thread's context, on a callback).
 static int
@@ -85,6 +94,15 @@
 
 static void *
 ncfdplane_thread(void* vncfp){
+#ifdef __ANDROID__
+  struct sigaction actions;
+  memset(&actions, 0, sizeof(actions));
+  sigemptyset(&actions.sa_mask);
+  actions.sa_flags = 0;
+  actions.sa_handler = thread_signal_handler;
+  sigaction(SIGUSR2, &actions, NULL);
+#endif
+
   fdthread(vncfp, -1);
   return NULL;
 }
@@ -266,6 +284,15 @@
 // need a poll on both main fd and pidfd
 static void *
 ncsubproc_thread(void* vncsp){
+#ifdef __ANDROID__
+  struct sigaction actions;
+  memset(&actions, 0, sizeof(actions));
+  sigemptyset(&actions.sa_mask);
+  actions.sa_flags = 0;
+  actions.sa_handler = thread_signal_handler;
+  sigaction(SIGUSR2, &actions, NULL);
+#endif
+
   int* status = malloc(sizeof(*status));
   if(status){
     ncsubproc* ncsp = vncsp;
@@ -287,6 +314,15 @@
 // wake up our poll()ing thread).
 static void *
 ncsubproc_waiter(void* vncsp){
+#ifdef __ANDROID__
+  struct sigaction actions;
+  memset(&actions, 0, sizeof(actions));
+  sigemptyset(&actions.sa_mask);
+  actions.sa_flags = 0;
+  actions.sa_handler = thread_signal_handler;
+  sigaction(SIGUSR2, &actions, NULL);
+#endif
+
   ncsubproc* ncsp = vncsp;
   int* status = malloc(sizeof(*status));
   pid_t pid;
@@ -425,7 +461,11 @@
     // then exits. don't try to cancel the thread in that case; rely instead on
     // killing the subprocess.
     if(n->pidfd < 0){
+#ifndef __ANDROID__
       pthread_cancel(n->nfp->tid);
+#else
+      pthread_kill(n->nfp->tid, SIGUSR2);
+#endif
       // shouldn't need a cancellation of waittid thanks to SIGKILL
       pthread_join(n->waittid, &vret);
     }
--- a/src/lib/in.c
+++ b/src/lib/in.c
@@ -7,6 +7,15 @@
 #include "render.h"
 #include "in.h"
 
+#ifdef __ANDROID__
+#define PTHREAD_CANCELED ((void *)-1)
+static void
+thread_signal_handler(int signum)
+{
+  pthread_exit(PTHREAD_CANCELED);
+}
+#endif
+
 // Notcurses takes over stdin, and if it is not connected to a terminal, also
 // tries to make a connection to the controlling terminal. If such a connection
 // is made, it will read from that source (in addition to stdin). We dump one or
@@ -2498,6 +2507,14 @@
 static void*
 input_thread(void* vmarshall){
   setup_alt_sig_stack();
+#ifdef __ANDROID__
+  struct sigaction actions;
+  memset(&actions, 0, sizeof(actions));
+  sigemptyset(&actions.sa_mask);
+  actions.sa_flags = SA_ONSTACK;
+  actions.sa_handler = thread_signal_handler;
+  sigaction(SIGUSR2, &actions, NULL);
+#endif
   inputctx* ictx = vmarshall;
   if(prep_all_keys(ictx) || build_cflow_automaton(ictx)){
     ictx->failed = true;
--- a/src/lib/internal.h
+++ b/src/lib/internal.h
@@ -1832,9 +1832,13 @@
 // have already exited), and then join it (an error here is propagated).
 static inline int
 cancel_and_join(const char* name, pthread_t tid, void** res){
+#ifndef __ANDROID__
   if(pthread_cancel(tid)){
     logerror("couldn't cancel %s thread", name); // tid might have died
   }
+#else
+  pthread_kill(tid, SIGUSR2);
+#endif
   if(pthread_join(tid, res)){
     logerror("error joining %s thread", name);
     return -1;