2 files changed, 34 insertions, 12 deletions

diff --git a/src/utils.c b/src/utils.c
index 28664d4..e30a0b3 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -30,6 +30,7 @@
 #include <stdarg.h>
 #include <time.h>
 #include <sys/time.h>
+#include <errno.h>
 #ifdef __APPLE__
 #include <mach/mach_time.h>
 #endif
@@ -214,7 +215,7 @@ char *string_concat(const char *str, ...)
         return result;
 }
 
-void buffer_read_from_filename(const char *filename, char **buffer, uint64_t *length)
+int buffer_read_from_filename(const char *filename, char **buffer, uint64_t *length)
 {
         FILE *f;
         uint64_t size;
@@ -223,7 +224,7 @@ void buffer_read_from_filename(const char *filename, char **buffer, uint64_t *le
 
         f = fopen(filename, "rb");
         if (!f) {
-                return;
+                return 0;
         }
 
         fseek(f, 0, SEEK_END);
@@ -232,26 +233,49 @@ void buffer_read_from_filename(const char *filename, char **buffer, uint64_t *le
 
         if (size == 0) {
                 fclose(f);
-                return;
+                return 0;
         }
 
         *buffer = (char*)malloc(sizeof(char)*(size+1));
+
+        if (!buffer) {
+                return 0;
+        }
+
+        int ret = 1;
         if (fread(*buffer, sizeof(char), size, f) != size) {
                 usbmuxd_log(LL_ERROR, "%s: ERROR: couldn't read %d bytes from %s", __func__, (int)size, filename);
+                free(buffer);
+                ret = 0;
+                errno = EIO;
         }
         fclose(f);
 
         *length = size;
+        return ret;
 }
 
-void buffer_write_to_filename(const char *filename, const char *buffer, uint64_t length)
+int buffer_write_to_filename(const char *filename, const char *buffer, uint64_t length)
 {
         FILE *f;
 
         f = fopen(filename, "wb");
         if (f) {
-                fwrite(buffer, sizeof(char), length, f);
+                size_t written = fwrite(buffer, sizeof(char), length, f);
                 fclose(f);
+
+                if (written == length) {
+                        return 1;
+                }
+                else {
+                        // Not all data could be written.
+                        errno = EIO;
+                        return 0;
+                }
+        }
+        else {
+                // Failed to open the file, let the caller know.
+                return 0;
         }
 }
 
@@ -263,9 +287,7 @@ int plist_read_from_filename(plist_t *plist, const char *filename)
         if (!filename)
                 return 0;
 
-        buffer_read_from_filename(filename, &buffer, &length);
-
-        if (!buffer) {
+        if (!buffer_read_from_filename(filename, &buffer, &length)) {
                 return 0;
         }
 
@@ -295,11 +317,11 @@ int plist_write_to_filename(plist_t plist, const char *filename, enum plist_form
         else
                 return 0;
 
-        buffer_write_to_filename(filename, buffer, length);
+        int res  = buffer_write_to_filename(filename, buffer, length);
 
         free(buffer);
 
-        return 1;
+        return res;
 }
 
 #ifndef HAVE_CLOCK_GETTIME
diff --git a/src/utils.h b/src/utils.h
index 1137a93..b5cab3f 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -75,8 +75,8 @@ char *stpcpy(char * s1, const char * s2);
 #endif
 char *string_concat(const char *str, ...);
 
-void buffer_read_from_filename(const char *filename, char **buffer, uint64_t *length);
-void buffer_write_to_filename(const char *filename, const char *buffer, uint64_t length);
+int buffer_read_from_filename(const char *filename, char **buffer, uint64_t *length);
+int buffer_write_to_filename(const char *filename, const char *buffer, uint64_t length);
 
 enum plist_format_t {
         PLIST_FORMAT_XML,