handle eintr (in places where it might be needed. not all places yet)

1 files changed, 63 insertions, 10 deletions

diff --git a/src/Storage.cpp b/src/Storage.cpp
index 8ef8e5f..50d1ffd 100644
--- a/src/Storage.cpp
+++ b/src/Storage.cpp
@@ -16,11 +16,57 @@
 #include <sys/types.h>
 #include <fcntl.h>
 
+#define EINTR_RETRY(ret, expr)              \
+    do {                                    \
+        errno = 0;                          \
+        while(true) {                       \
+            ret = (expr);                   \
+            if(ret != -1 || errno != EINTR) \
+                break;                      \
+        }                                   \
+    } while(0)
+
 static int makedir(const char *path) {
     return mkdir(path, S_IRWXU);
 }
 
 namespace QuickMedia {
+    static FILE* fopen_eintr(const char *filename, const char *modes) {
+        errno = 0;
+        while(true) {
+            FILE *f = fopen(filename, modes);
+            if(f || errno != EINTR)
+                return f;
+        }
+    }   
+
+    static size_t fwrite_eintr(const char *data, size_t size, FILE *f) {
+        errno = 0;
+        while(true) {
+            const size_t r = fwrite(data, 1, size, f); 
+            if(r == size || errno != EINTR)
+                return r;
+        }
+    }   
+
+    static size_t fread_eintr(char *data, size_t size, FILE *f) {
+        errno = 0;
+        while(true) {
+            const size_t r = fread(data, 1, size, f); 
+            if(r == size || errno != EINTR)
+                return r;
+        }
+    }   
+
+    static size_t fseek_eintr(FILE *f, long offset, int whence) {
+        errno = 0;
+        while(true) {
+            const int r = fseek(f, offset, whence);
+            if(r == 0 || errno != EINTR)
+                return r;
+        }
+    }
+
     Path get_home_dir()
     {
         const char *homeDir = getenv("HOME");
@@ -81,37 +127,42 @@ namespace QuickMedia {
 
     FileType get_file_type(const Path &path) {
         struct stat file_stat;
-        if(stat(path.data.c_str(), &file_stat) == 0)
+        int ret;
+        EINTR_RETRY(ret, stat(path.data.c_str(), &file_stat));
+        if(ret == 0)
             return S_ISREG(file_stat.st_mode) ? FileType::REGULAR : FileType::DIRECTORY;
         return FileType::FILE_NOT_FOUND;
     }
 
     int file_get_content(const Path &path, std::string &result) {
-        FILE *file = fopen(path.data.c_str(), "rb");
+        FILE *file = fopen_eintr(path.data.c_str(), "rb");
         if(!file)
             return -errno;
         
-        fseek(file, 0, SEEK_END);
+        fseek_eintr(file, 0, SEEK_END);
         long file_size = ftell(file);
         if(file_size == -1) {
             fprintf(stderr, "Error: attempted to read directory %s as a file\n", path.data.c_str());
             fclose(file);
             return -1;
         }
-        fseek(file, 0, SEEK_SET);
+        fseek_eintr(file, 0, SEEK_SET);
 
         result.resize(file_size);
-        if(fread(&result[0], 1, file_size, file) != (size_t)file_size) {
+        if(fread_eintr(&result[0], file_size, file) != (size_t)file_size) {
             fclose(file);
             return -1;
         }
 
-        return fclose(file);
+        fclose(file);
+        return 0;
     }
 
     int file_get_size(const Path &path, size_t *size) {
         struct stat file_stat;
-        if(stat(path.data.c_str(), &file_stat) == 0 && S_ISREG(file_stat.st_mode)) {
+        int ret;
+        EINTR_RETRY(ret, stat(path.data.c_str(), &file_stat));
+        if(ret == 0 && S_ISREG(file_stat.st_mode)) {
             *size = file_stat.st_size;
             return 0;
         }
@@ -121,7 +172,9 @@ namespace QuickMedia {
 
     bool file_get_last_modified_time_seconds(const char *path, time_t *result) {
         struct stat file_stat;
-        if(stat(path, &file_stat) == 0) {
+        int ret;
+        EINTR_RETRY(ret, stat(path, &file_stat));
+        if(ret == 0) {
             *result = file_stat.st_mtim.tv_sec;
             return true;
         }
@@ -129,13 +182,13 @@ namespace QuickMedia {
     }
 
     static int file_overwrite(const Path &path, const char *str, size_t size) {
-        FILE *file = fopen(path.data.c_str(), "wb");
+        FILE *file = fopen_eintr(path.data.c_str(), "wb");
         if(!file) {
             perror(path.data.c_str());
             return -1;
         }
         
-        if(fwrite(str, 1, size, file) != size) {
+        if(fwrite_eintr(str, size, file) != size) {
             fclose(file);
             return -1;
         }