Make pipes blocking

src/kernel/keyboard.c

@@ -1,5 +1,6 @@
 #include "src/kernel/keyboard.h"
 #include "src/kernel/idt.h"
+#include "src/kernel/process.h"
 #include "src/kernel/stream.h"
 #include "src/kernel/util.h"
 #include "src/lib/memory.h"
@@ -56,8 +57,10 @@ static uint64_t stream_write(__attribute__((unused)) const stream_t *self, __att
 }
 
 static uint64_t stream_read(__attribute__((unused)) const stream_t *self, uint64_t max, char *to) {
-  if (max == 0 || buffer_length == 0) {
-    return 0;
+  while (!buffer_length) {
+    __asm__ volatile("sti");
+    process_next();
+    __asm__ volatile("cli");
   }
 
   uint64_t size = buffer_length > max ? max : buffer_length;

src/kernel/pipe.c

@@ -1,4 +1,5 @@
 #include "src/kernel/pipe.h"
+#include "src/kernel/process.h"
 #include "src/kernel/stream.h"
 #include "src/lib/memory.h"
 
@@ -35,16 +36,17 @@ static uint64_t null_write(__attribute__((unused)) const stream_t *self, __attri
 static uint64_t pipe_read(const stream_t *self, uint64_t max, char *to) {
   pipe_t *pipe = ((pipe_read_stream_t *)self)->pipe;
 
-  uint64_t available = (pipe->end + PIPE_BUFFER_SIZE - pipe->begin) % PIPE_BUFFER_SIZE;
-  uint64_t to_read = available < max ? available : max;
-
-  if (pipe->write_closed && !to_read) {
-    return (uint64_t)-1;
+  while (pipe->begin == pipe->end) {
+    if (pipe->write_closed) {
+      return 0;
+    }
+    __asm__ volatile("sti");
+    process_next();
+    __asm__ volatile("cli");
   }
 
-  if (!to_read) {
-    return 0;
-  }
+  uint64_t available = (pipe->end + PIPE_BUFFER_SIZE - pipe->begin) % PIPE_BUFFER_SIZE;
+  uint64_t to_read = available < max ? available : max;
 
   if (pipe->begin + to_read <= PIPE_BUFFER_SIZE) {
     memory_copy(pipe->buffer + pipe->begin, to_read, to);
@@ -61,27 +63,33 @@ static uint64_t pipe_read(const stream_t *self, uint64_t max, char *to) {
 static uint64_t pipe_write(const stream_t *self, const char *from, uint64_t bytes) {
   pipe_t *pipe = ((pipe_read_stream_t *)self)->pipe;
 
-  if (pipe->read_closed) {
-    return (uint64_t)-1;
-  }
-
-  uint64_t available = PIPE_BUFFER_SIZE - (pipe->end + PIPE_BUFFER_SIZE - pipe->begin) % PIPE_BUFFER_SIZE;
-  uint64_t to_write = available < bytes ? available : bytes;
-
-  if (to_write == 0) {
-    return 0;
-  }
-
-  if (pipe->end + to_write <= PIPE_BUFFER_SIZE) {
-    memory_copy(from, to_write, pipe->buffer + pipe->end);
-  } else {
-    uint64_t chunk = PIPE_BUFFER_SIZE - pipe->end;
-    memory_copy(from, chunk, pipe->buffer + pipe->end);
-    memory_copy(from + chunk, to_write - chunk, pipe->buffer);
+  uint64_t written = 0;
+  while (written < bytes) {
+    while (((pipe->end + 1) % PIPE_BUFFER_SIZE) == pipe->begin) {
+      if (pipe->read_closed) {
+        return written;
+      }
+      __asm__ volatile("sti");
+      process_next();
+      __asm__ volatile("cli");
+    }
+
+    uint64_t available = PIPE_BUFFER_SIZE - (pipe->end + PIPE_BUFFER_SIZE - pipe->begin) % PIPE_BUFFER_SIZE - 1;
+    uint64_t to_write = available < bytes - written ? available : bytes - written;
+
+    if (pipe->end + to_write <= PIPE_BUFFER_SIZE) {
+      memory_copy(from, to_write, pipe->buffer + pipe->end);
+    } else {
+      uint64_t chunk = PIPE_BUFFER_SIZE - pipe->end;
+      memory_copy(from, chunk, pipe->buffer + pipe->end);
+      memory_copy(from + chunk, to_write - chunk, pipe->buffer);
+    }
+
+    pipe->end = (pipe->end + to_write) % PIPE_BUFFER_SIZE;
+    written += to_write;
   }
 
-  pipe->end = (pipe->end + to_write) % PIPE_BUFFER_SIZE;
-  return to_write;
+  return written;
 }
 
 static void read_close(stream_t *self) {

src/kernel/process.c

@@ -126,7 +126,9 @@ void process_next() {
   process_t *prev = current_process;
   tss.rsp0 = (uint64_t)next->kernel_stack;
   current_process = next;
+  __asm__ volatile("cli");
   process_switch_to(&prev->kernel_rsp, next->kernel_rsp, VIRT_TO_PHYS(next->pml4));
+  __asm__ volatile("sti");
 }
 
 void process_destroy(process_t *proc) {

src/kernel/syscall.c

@@ -4,7 +4,6 @@
 #include "src/kernel/path.h"
 #include "src/kernel/process.h"
 #include "src/kernel/stream.h"
-#include "src/kernel/tss.h"
 #include "src/lib/layout.h"
 #include "src/lib/memory.h"
 #include "src/lib/string.h"

src/user/app/shell/shell.c

@@ -108,16 +108,14 @@ uint64_t main() {
   char chunk[64];
   uint64_t received;
 
-  while (1) {
-    if ((received = read(0, sizeof(chunk), chunk))) {
-      for (uint64_t i = 0; i < received; i++) {
-        if (chunk[i] == '\n') {
-          line[offset] = '\0';
-          execute(line);
-          offset = 0;
-        } else if (offset < 255) {
-          line[offset++] = chunk[i];
-        }
+  while ((received = read(0, sizeof(chunk), chunk))) {
+    for (uint64_t i = 0; i < received; i++) {
+      if (chunk[i] == '\n') {
+        line[offset] = '\0';
+        execute(line);
+        offset = 0;
+      } else if (offset < 255) {
+        line[offset++] = chunk[i];
       }
     }
   }

src/user/app/terminal/terminal.c

@@ -196,11 +196,9 @@ uint64_t main() {
   memory_set('\b', PROMPT_LENGTH, (char *)bs);
   memory_set(' ', PROMPT_LENGTH, (char *)ws);
 
-  while (1) {
-    char c;
-    if (read(0, 1, &c)) {
-      on_char_received(c);
-    }
+  char c;
+  while (read(0, 1, &c)) {
+    on_char_received(c);
   }
 
   return 0;