portable error reporting for memory API

GrapheneOS · Mar 22, 2021 · 29ffcdf · 29ffcdf
1 parent f773a96
commit 29ffcdf
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Showing 2 changed files with 33 additions and 38 deletions.
diff --git a/memory.c b/memory.c
@@ -25,74 +25,68 @@ void *memory_map(size_t size) {
     return p;
 }
 
-int memory_map_fixed(void *ptr, size_t size) {
+bool memory_map_fixed(void *ptr, size_t size) {
     void *p = mmap(ptr, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE|MAP_FIXED, -1, 0);
-    if (unlikely(p == MAP_FAILED)) {
-        if (errno != ENOMEM) {
-            fatal_error("non-ENOMEM MAP_FIXED mmap failure");
-        }
-        return 1;
+    bool ret = p == MAP_FAILED;
+    if (unlikely(ret) && errno != ENOMEM) {
+        fatal_error("non-ENOMEM MAP_FIXED mmap failure");
     }
-    return 0;
+    return ret;
 }
 
-int memory_unmap(void *ptr, size_t size) {
-    int ret = munmap(ptr, size);
+bool memory_unmap(void *ptr, size_t size) {
+    bool ret = munmap(ptr, size);
     if (unlikely(ret) && errno != ENOMEM) {
         fatal_error("non-ENOMEM munmap failure");
     }
     return ret;
 }
 
-static int memory_protect_prot(void *ptr, size_t size, int prot, UNUSED int pkey) {
+static bool memory_protect_prot(void *ptr, size_t size, int prot, UNUSED int pkey) {
 #ifdef USE_PKEY
-    int ret = pkey_mprotect(ptr, size, prot, pkey);
+    bool ret = pkey_mprotect(ptr, size, prot, pkey);
 #else
-    int ret = mprotect(ptr, size, prot);
+    bool ret = mprotect(ptr, size, prot);
 #endif
     if (unlikely(ret) && errno != ENOMEM) {
         fatal_error("non-ENOMEM mprotect failure");
     }
     return ret;
 }
 
-int memory_protect_ro(void *ptr, size_t size) {
+bool memory_protect_ro(void *ptr, size_t size) {
     return memory_protect_prot(ptr, size, PROT_READ, -1);
 }
 
-int memory_protect_rw(void *ptr, size_t size) {
+bool memory_protect_rw(void *ptr, size_t size) {
     return memory_protect_prot(ptr, size, PROT_READ|PROT_WRITE, -1);
 }
 
-int memory_protect_rw_metadata(void *ptr, size_t size) {
+bool memory_protect_rw_metadata(void *ptr, size_t size) {
     return memory_protect_prot(ptr, size, PROT_READ|PROT_WRITE, get_metadata_key());
 }
 
 #ifdef HAVE_COMPATIBLE_MREMAP
-int memory_remap(void *old, size_t old_size, size_t new_size) {
+bool memory_remap(void *old, size_t old_size, size_t new_size) {
     void *ptr = mremap(old, old_size, new_size, 0);
-    if (unlikely(ptr == MAP_FAILED)) {
-        if (errno != ENOMEM) {
-            fatal_error("non-ENOMEM mremap failure");
-        }
-        return 1;
+    bool ret = ptr == MAP_FAILED;
+    if (unlikely(ret) && errno != ENOMEM) {
+        fatal_error("non-ENOMEM mremap failure");
     }
-    return 0;
+    return ret;
 }
 
-int memory_remap_fixed(void *old, size_t old_size, void *new, size_t new_size) {
+bool memory_remap_fixed(void *old, size_t old_size, void *new, size_t new_size) {
     void *ptr = mremap(old, old_size, new_size, MREMAP_MAYMOVE|MREMAP_FIXED, new);
-    if (unlikely(ptr == MAP_FAILED)) {
-        if (errno != ENOMEM) {
-            fatal_error("non-ENOMEM MREMAP_FIXED mremap failure");
-        }
-        return 1;
+    bool ret = ptr == MAP_FAILED;
+    if (unlikely(ret) && errno != ENOMEM) {
+        fatal_error("non-ENOMEM MREMAP_FIXED mremap failure");
     }
-    return 0;
+    return ret;
 }
 #endif
 
-int memory_purge(void *ptr, size_t size) {
+bool memory_purge(void *ptr, size_t size) {
     int ret = madvise(ptr, size, MADV_DONTNEED);
     if (unlikely(ret) && errno != ENOMEM) {
         fatal_error("non-ENOMEM MADV_DONTNEED madvise failure");

diff --git a/memory.h b/memory.h
@@ -1,6 +1,7 @@
 #ifndef MEMORY_H
 #define MEMORY_H
 
+#include <stdbool.h>
 #include <stddef.h>
 
 #ifdef __linux__
@@ -10,16 +11,16 @@
 int get_metadata_key(void);
 
 void *memory_map(size_t size);
-int memory_map_fixed(void *ptr, size_t size);
-int memory_unmap(void *ptr, size_t size);
-int memory_protect_ro(void *ptr, size_t size);
-int memory_protect_rw(void *ptr, size_t size);
-int memory_protect_rw_metadata(void *ptr, size_t size);
+bool memory_map_fixed(void *ptr, size_t size);
+bool memory_unmap(void *ptr, size_t size);
+bool memory_protect_ro(void *ptr, size_t size);
+bool memory_protect_rw(void *ptr, size_t size);
+bool memory_protect_rw_metadata(void *ptr, size_t size);
 #ifdef HAVE_COMPATIBLE_MREMAP
-int memory_remap(void *old, size_t old_size, size_t new_size);
-int memory_remap_fixed(void *old, size_t old_size, void *new, size_t new_size);
+bool memory_remap(void *old, size_t old_size, size_t new_size);
+bool memory_remap_fixed(void *old, size_t old_size, void *new, size_t new_size);
 #endif
-int memory_purge(void *ptr, size_t size);
+bool memory_purge(void *ptr, size_t size);
 void memory_set_name(void *ptr, size_t size, const char *name);
 
 #endif