added:

* coroutines
 * string
modified:
 * http: fixed a couple of bugs
 * strutils: renamed to os, it is now a header for some generic platform-indipendent code
 * tracelog: added option to not print newline at the end of a message + bug fixes

coroutine.h

@@ -0,0 +1,127 @@
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdbool.h> // bool
+#include <string.h>  // memset
+
+// heavily inspired by https://gist.github.com/Enichan/5f01140530ff0133fde19c9549a2a973
+
+#if 0
+// Usage example:
+typedef struct {
+    int result;
+    coroutine_t co;
+} co_int_t;
+
+bool coVoid(co_void_t *co) {
+    costate(co_nostate);
+    coroutine({
+        printf("hello");    yield();
+        printf("world");    yield();
+        printf("how");      yield();
+        printf("is");       yield();
+        printf("it");       yield();
+        printf("going?\n");
+    });
+}
+
+bool countToTen(co_int_t *co) {
+    costate(int i; int ii;);
+    coroutine({
+        for(self.i = 0; self.i < 10; ++self.i) {
+            self.ii += self.i;
+            yieldVal(self.ii);
+        }
+    });
+}
+
+int main() {
+    co_void_t covoid = {0};
+    while(coVoid(&covoid)) {
+        printf(" ");
+    }
+
+    co_int_t coint;
+    coint.co = coInit();
+    while(countToTen(&coint)) {
+        printf("%d ", coint.result);
+    }
+    printf("\n");
+    // reset coroutine for next call
+    coint.co = coInit();
+    while(countToTen(&coint)) {
+        printf("%d ", coint.result);
+    }
+    printf("\n");
+}
+#endif
+
+typedef struct {
+    int state;
+} coroutine_t;
+
+typedef struct {
+    coroutine_t co;
+} co_void_t;
+
+coroutine_t coInit();
+bool coIsDead(coroutine_t co);
+
+#define COVAR co
+#define COSELF self
+
+#define costate(...) \
+    typedef struct { bool init; __VA_ARGS__ } COSTATE; \
+    static COSTATE self = {0}
+
+#define co_nostate { char __dummy__; }
+
+#define yieldBreak()      \
+    COVAR->co.state = -1; \
+    self.init = false;    \
+    return false;
+
+#define coroutine(...)                  \
+    if(!self.init) {                    \
+        memset(&self, 0, sizeof(self)); \
+        self.init = true;               \
+    }                                   \
+    switch(COVAR->co.state) {           \
+        case 0:;                        \
+            __VA_ARGS__                 \
+    }                                   \
+    yieldBreak();
+
+#define yield() _yield(__COUNTER__)
+#define _yield(count)            \
+    do {                         \
+        COVAR->co.state = count; \
+        return true;             \
+    case count:;                 \
+    } while(0);             
+
+#define yieldVal(v) _yieldVal(v, __COUNTER__)
+#define _yieldVal(v, count)      \
+    do {                         \
+        COVAR->co.state = count; \
+        COVAR->result = v;       \
+        return true;             \
+    case count:;                 \
+    } while(0);             
+
+// increment __COUNTER__ past 0 so we don't get double case errors
+#define CONCAT_IMPL(x, y) x##y
+#define MACRO_CONCAT(x, y) CONCAT_IMPL(x, y)
+#define __INC_COUNTER int MACRO_CONCAT(__counter_tmp_, __COUNTER__)
+__INC_COUNTER;
+
+#undef CONCAT_IMPL
+#undef MACRO_CONCAT
+#undef __INC_COUNTER
+
+#ifdef __cplusplus
+} // extern "C"
+#endif