OS1 K september 2020: Update solution, 2->4 spaces

siwiki · Apr 29, 2023 · 8be4af3 · 8be4af3
1 parent fbd8dc3
commit 8be4af3
Showing 1 changed file with 49 additions and 59 deletions.
diff --git a/os1/2020/9/k-sol.md b/os1/2020/9/k-sol.md
@@ -2,42 +2,33 @@
 --------------------------------------------------------------------------------
 context
 ```cpp
-Thread* t_fork () {
-  lock();
-  if (setjmp(Thread::running->context)==0) {
-
-    // Parent thread:
+Thread* t_fork() {
+    lock();
     // Allocate a new stack:
     void* stck = malloc(STACK_SIZE);
     if (!stck) throw ThreadCreationException();
     // and copy its contents from the parent's stack:
-    memcpy(stck,Thread::running->stack,STACK_SIZE);
-
+    memcpy(stck, Thread::running->stack, STACK_SIZE);
     // Create a new Thread object:
     Thread* newThr = new Thread();
-    if (!newThr) { free(stck);  throw ThreadCreationException(); }
+    if (!newThr) {
+        free(stck);
+        throw ThreadCreationException();
+    }
     newThr->stack = stck;
-
-    if (setjmp(newThr->context)==0) {
-      // Parent thread:
-      // and set its stack pointer:
-      newThr->context->sp = newThr->context->sp -
-                            Thread::running->stack + stck;
-      // Put the new thread to the ready list and return:
-      Scheduler::put(newThr);
-      unlock();
-      return newThr;
+    if (setjmp(newThr->context) == 0) {
+        // Parent thread:
+        // and set its stack pointer:
+        newThr->context->sp = newThr->context->sp - Thread::running->stack + stck;
+        // Put the new thread to the ready list and return:
+        Scheduler::put(newThr);
+        unlock();
+        return newThr;
     } else {
-      // Child thread:
-      unlock();
-      return 0;
+        // Child thread:
+        unlock();
+        return 0;
     }
-
-  } else {
-    // Child thread:
-    unlock();
-    return 0;
-  }
 }
 ```
 
@@ -46,49 +37,48 @@ syscall
 ```cpp
 typedef void (*PF)(void*);
 
-void cobegin (PF f[], void* af[], int n) {
-  int* ids = new int[n];
-  for (int i=0; i<n; i++)
-    if ((ids[i]=fork())==0) {
-      pf[i](af[i]);
-      exit();
-    }
-  for (int i=0; i<n; i++)
-    wait(ids[i]);
-  delete ids;
+void cobegin(PF f[], void* af[], int n) {
+    int* ids = new int[n];
+    for (int i = 0; i < n; i++)
+        if ((ids[i] = fork()) == 0) {
+            pf[i](af[i]);
+            exit();
+        }
+    for (int i = 0; i < n; i++)
+        wait(ids[i]);
+    delete ids;
 }
 ```
 
 --------------------------------------------------------------------------------
 segment
 ```cpp
-SegDesc* findSegDesc (SegDesc* root, size_t size) {
-  SegDesc* sd = root;
-  while (sd != nullptr) {
-    if (sd->sz >= size) return sd;
-    else sd = sd->right;
-  }
-  return nullptr;
+SegDesc* findSegDesc(SegDesc* root, size_t size) {
+    SegDesc* sd = root;
+    while (sd != nullptr) {
+        if (sd->sz >= size) return sd;
+        else sd = sd->right;
+    }
+    return nullptr;
 }
 ```
 
 --------------------------------------------------------------------------------
 fsimpl
 ```cpp
-void truncateFile (FCB* fcb) {
-  for (size_t i=0; i<SingleIndexSize; i++)
-    if (fcb->singleIndex[i]) {
-      freeBlock(fcb->singleIndex[i]);
-      fcb->singleIndex[i] = 0;
+void truncateFile(FCB* fcb) {
+    for (size_t i = 0; i < SingleIndexSize; i++)
+        if (fcb->singleIndex[i]) {
+            freeBlock(fcb->singleIndex[i]);
+            fcb->singleIndex[i] = 0;
+        }
+    if (fcb->dblIndex) {
+        PBlock* dblIx = (PBlock*)getBlock(fcb->dblIndex);
+        for (size_t i = 0; i < DblIndexSize; i++)
+            if (dblIx[i]) freeBlock(dblIx[i]);
+        freeBlock(fcb->dblIndex);
+        fcb->dblIndex = 0;
     }
-
-  if (fcb->dblIndex) {
-    PBlock* dblIx = (PBlock*)getBlock(fcb->dblIndex);
-    for (size_t i=0; i<DblIndexSize; i++)
-      if (dblIx[i]) freeBlock(dblIx[i]);
-    freeBlock(fcb->dblIndex);
-    fcb->dblIndex = 0;
-  }
-
-  fcb->size = 0;
+    fcb->size = 0;
+}
 ```