types, vm: refactor usage of global variables

Introduce an extensible private TLS context structure and use it within
libucode to store global state such as active object iterators.

This allows using libucode concurrently in multiple threads without
unintentionally sharing global state among them.

Also adjust the signal dispatching setup logic in `uc_vm_init()` to only
enable signal handling if no other VM in the same thread already handles
signals.

Suggested-by: Isaac de Wolff <idewolff@vincitech.nl>
[squash commits, move signal handler vm pointer and object iterator list
 into common extensible TLS context, whitespace and naming adjustments,
 extended signal setup logic]
Signed-off-by: Jo-Philipp Wich <jo@mein.io>

1 files changed, 25 insertions, 25 deletions

diff --git a/tests/custom/03_stdlib/60_gc b/tests/custom/03_stdlib/60_gc
index 28c0d00..44e5d9e 100644
--- a/tests/custom/03_stdlib/60_gc
+++ b/tests/custom/03_stdlib/60_gc
@@ -45,11 +45,11 @@ Returns an object count if the given operation is `count`.
 -- End --
 
 -- Expect stdout --
-Count #1: 6
-Count #2: 7
-Count #3: 6
-Count #4: 7
-Count #5: 6
+Count #1: 5
+Count #2: 6
+Count #3: 5
+Count #4: 6
+Count #5: 5
 -- End --
 
 
@@ -84,24 +84,24 @@ Testing enabling the automatic collector.
 -- End --
 
 -- Expect stdout --
-Count #1: 7
-Count #2: 14
-Count #3: 14
-Count #4: 14
-Count #5: 14
-Count #6: 14
-Count #7: 14
-Count #8: 14
-Count #9: 14
-Count #10: 14
-Count #11: 14
-Count #12: 24
-Count #13: 34
-Count #14: 44
-Count #15: 54
-Count #16: 64
-Count #17: 74
-Count #18: 84
-Count #19: 94
-Count #20: 104
+Count #1: 6
+Count #2: 12
+Count #3: 12
+Count #4: 12
+Count #5: 12
+Count #6: 12
+Count #7: 12
+Count #8: 12
+Count #9: 12
+Count #10: 12
+Count #11: 12
+Count #12: 22
+Count #13: 32
+Count #14: 42
+Count #15: 52
+Count #16: 62
+Count #17: 72
+Count #18: 82
+Count #19: 92
+Count #20: 102
 -- End --