1 files changed, 113 insertions, 0 deletions
diff --git a/src/ioport.c b/src/ioport.c
new file mode 100644
index 0000000..a77e564
--- /dev/null
+++ b/src/ioport.c
@@ -0,0 +1,113 @@
+#include <ioport.h>
+#ifdef CONFIG_IOPORTS
+#ifdef CONFIG_PCINT
+
+struct PCIW {
+    uint8_t flags;
+    uint8_t mask;
+    void (*change) (uint8_t group, uint8_t mask);
+};
+
+// Exploiting implementation of libc malloc
+#define PCIW_LEN(INPCIW) (*((uint16_t *) INPCIW - 1) / sizeof(struct PCIW) - 1)
+
+#if (defined MCUSUPPORT_PCINT0 && defined MCUSUPPORT_PCINT1 && defined MCUSUPPORT_PCINT2)
+#define PCI_COUNT 3
+#elif (defined MCUSUPPORT_PCINT0 && defined MCUSUPPORT_PCINT1 || \
+        defined MCUSUPPORT_PCINT1 && defined MCUSUPPORT_PCINT2 || \
+        defined MCUSUPPORT_PCINT2 && defined MCUSUPPORT_PCINT0)
+#define PCI_COUNT 2
+#elif (defined MCUSUPPORT_PCINT0 || defined MCUSUPPORT_PCINT1 || defined MCUSUPPORT_PCINT2)
+#define PCI_COUNT 1
+#else
+#define PCI_COUNT 0
+#endif
+
+#define GROUP2INDEX(GRP) (GRP - MCUSUPPORT_PCINT0)
+
+static struct PCIW *pciw[PCI_COUNT];
+static uint8_t pci_state[PCI_COUNT];
+static void pci(int8_t group, int8_t pinmax) {
+    int8_t i, y;
+    int8_t index = GROUP2INDEX(group);
+    int8_t len = (int8_t) PCIW_LEN(pciw[index]);
+    // WARN Is possible that PCINT0 is not corresponding with B group and so on?
+    uint8_t state = IOE_IO_PIN(group);
+    for (i = len; i >= 0; i--) {
+        uint8_t stA = state & pciw[index][i].mask;
+        uint8_t stB = pci_state[index] & pciw[index][i].mask;
+        if (((~stA & stB) && pciw[index][i].flags & IOE_IO_RISING) ||
+            ((stA & ~stB) && pciw[index][i].flags & IOE_IO_FALLING)) {
+            pciw[index][i].change(IOE_IO_B, mask);
+        }
+    }
+    pci_state[index] = state;
+}
+
+void io_change_sethook(uint8_t group, uint8_t mask, uint8_t edge,
+                       void (*change) (uint8_t group, uint8_t mask)) {
+    int8_t index = (int8_t) GROUP2INDEX(group);
+    int8_t len = (int8_t) PCIW_LEN(pciw[index]);
+    pciw[index] = realloc(pciw[index], len + 1);
+    pciw[index][len].flags = edge;
+    pciw[index][len].mask = mask;
+    pciw[index][len].change = change;
+    switch (group) {
+#ifdef MCUSUPPORT_PCINT0 // TODO this wont work with attiny4313 and meaby others
+    case IO_B:
+        PCICR |= (1<<0);
+        PCMSK0 |= mask;
+        break;
+#endif
+#ifdef MCUSUPPORT_PCINT1
+    case IO_C:
+        PCICR |= (1<<1);
+        PCMSK1 |= mask;
+        break;
+#endif
+#ifdef MCUSUPPORT_PCINT2
+    case IO_D:
+        PCICR |= (1<<2);
+        PCMSK2 |= mask;
+        break
+#endif
+    }
+}
+
+void io_change_remhook(void (*change) (uint8_t group, uint8_t mask)) {
+    int8_t i, y;
+    int8_t len;
+    for (i = PCI_COUNT - 1; i >= 0; i--) {
+        len = (int8_t)PCIW_LEN(pciw[index]);
+        for (y = len - 1; y >= 0; y--) {
+            if (pciw[i][y].change == change) {
+
+            }
+        }
+    }
+}
+
+void io_change_clearhooks(void) {
+}
+
+// WARN This will work only if C is only defined on MCU with also B defined.
+#ifdef MCUSUPPORT_PCINT0
+ISR(PCINT0_vect, ISR_BLOCK) {
+    pci(IO_B, MCUSUPPORT_PCINT0);
+}
+#endif /* MCUSUPPORT_PCINT0 */
+
+#ifdef MCUSUPPORT_PCINT1
+ISR(PCINT1_vect, ISR_BLOCK) {
+    pci(IO_C, MCUSUPPORT_PCINT1);
+}
+#endif /* MCUSUPPORT_PCINT1 */
+
+#ifdef MCUSUPPORT_PCINT2
+ISR(PCINT2_vect, ISR_BLOCK) {
+    pci(IO_D, MCUSUPPORT_PCINT2);
+}
+#endif /* MCUSUPPORT_PCINT2 */
+
+#endif /* CONFIG_PCINT */
+#endif /* CONFIG_IOPORTS */