Cleaner exception handling

src/calibre/utils/podofo/doc.cpp

@@ -744,16 +744,13 @@ static PyMethodDef PDFDoc_methods[] = {
     {"alter_links", (PyCFunction)PDFDoc_alter_links, METH_VARARGS,
      "alter_links() -> Change links in the document."
     },
-    {"list_fonts", (PyCFunction)list_fonts, METH_VARARGS,
+    {"list_fonts", (PyCFunction)py_list_fonts, METH_VARARGS,
      "list_fonts() -> Get list of fonts in document"
     },
-    {"remove_fonts", (PyCFunction)remove_fonts, METH_VARARGS,
+    {"remove_unused_fonts", (PyCFunction)py_remove_unused_fonts, METH_NOARGS,
-     "remove_fonts() -> Remove the specified font objects."
-    },
-    {"remove_unused_fonts", (PyCFunction)remove_unused_fonts, METH_NOARGS,
      "remove_unused_fonts() -> Remove unused font objects."
     },
-    {"merge_fonts", (PyCFunction)merge_fonts, METH_VARARGS,
+    {"merge_fonts", (PyCFunction)py_merge_fonts, METH_VARARGS,
      "merge_fonts() -> Merge the specified fonts."
     },
     {"delete_pages", (PyCFunction)PDFDoc_delete_pages, METH_VARARGS,

src/calibre/utils/podofo/fonts.cpp

@@ -11,6 +11,14 @@
 
 using namespace pdf;
 
+#define PYWRAP(name) extern "C" PyObject* py_##name(PDFDoc *self, PyObject *args) { \
+    try { \
+        return name(self, args); \
+    } catch (const PdfError &err) { podofo_set_exception(err); return NULL; \
+    } catch (const std::exception &err) { PyErr_Format(Error, "Error in %s(): %s", #name, err.what()); return NULL; \
+    } catch (...) { PyErr_SetString(Error, "An unknown error occurred in " #name); return NULL; } \
+}
+
 static inline PyObject*
 ref_as_tuple(const PdfReference &ref) {
     unsigned long num = ref.ObjectNumber(), generation = ref.GenerationNumber();
@@ -149,14 +157,12 @@ convert_w_array(PyObject *src, PdfArray &dest) {
     }
 }
 
-extern "C" {
+static PyObject*
-PyObject*
 list_fonts(PDFDoc *self, PyObject *args) {
     int get_font_data = 0;
     if (!PyArg_ParseTuple(args, "|i", &get_font_data)) return NULL;
     pyunique_ptr ans(PyList_New(0));
     if (!ans) return NULL;
-    try {
     const PdfVecObjects &objects = self->doc->GetObjects();
     for (TCIVecObjects it = objects.begin(); it != objects.end(); it++) {
         if ((*it)->IsDictionary()) {
@@ -223,36 +229,14 @@ list_fonts(PDFDoc *self, PyObject *args) {
             }
         }
     }
-    } catch (const PdfError &err) {
-        podofo_set_exception(err);
-        return NULL;
-    }
     return ans.release();
 }
 
-PyObject*
-remove_fonts(PDFDoc *self, PyObject *args) {
-    PyObject *fonts;
-    if (!PyArg_ParseTuple(args, "O!", &PyTuple_Type, &fonts)) return NULL;
-    PdfVecObjects &objects = self->doc->GetObjects();
-    for (Py_ssize_t i = 0; i < PyTuple_GET_SIZE(fonts); i++) {
-        unsigned long num, gen;
-        if (!PyArg_ParseTuple(PyTuple_GET_ITEM(fonts, i), "kk", &num, &gen)) return NULL;
-        PdfReference ref(num, gen);
-        PdfObject *font = objects.GetObject(ref);
-        if (font) {
-            remove_font(objects, font);
-        }
-    }
-    Py_RETURN_NONE;
-}
-
 typedef std::unordered_map<PdfReference, unsigned long, PdfReferenceHasher> charprocs_usage_map;
 
-PyObject*
+static PyObject*
 remove_unused_fonts(PDFDoc *self, PyObject *args) {
     unsigned long count = 0;
-    try {
     unordered_reference_set used_fonts;
     for (int i = 0; i < self->doc->GetPageCount(); i++) {
         PdfPage *page = self->doc->GetPage(i);
@@ -307,7 +291,6 @@ remove_unused_fonts(PDFDoc *self, PyObject *args) {
             delete objects.RemoveObject(x.first);
         }
     }
-    } catch(const PdfError &err) { podofo_set_exception(err); return NULL; }
 
     return Py_BuildValue("k", count);
 }
@@ -373,4 +356,6 @@ merge_fonts(PDFDoc *self, PyObject *args) {
     Py_RETURN_NONE;
 }
 
-}
+PYWRAP(list_fonts)
+PYWRAP(merge_fonts)
+PYWRAP(remove_unused_fonts)

src/calibre/utils/podofo/global.h

@@ -96,9 +96,8 @@ typedef std::unordered_set<PdfReference, PdfReferenceHasher> unordered_reference
 
 
 extern "C" {
-PyObject* list_fonts(PDFDoc*, PyObject*);
+PyObject* py_list_fonts(PDFDoc*, PyObject*);
-PyObject* remove_fonts(PDFDoc *self, PyObject *args);
+PyObject* py_remove_unused_fonts(PDFDoc *self, PyObject *args);
-PyObject* remove_unused_fonts(PDFDoc *self, PyObject *args);
+PyObject* py_merge_fonts(PDFDoc *self, PyObject *args);
-PyObject* merge_fonts(PDFDoc *self, PyObject *args);
 }
 }