Add QUtil::read_file_into_memory

This code was essentially duplicated between test_driver and
standalone_fuzz_target_runner.

ChangeLog

@@ -1,3 +1,7 @@
+2019-06-22  Jay Berkenbilt  <ejb@ql.org>
+
+	* Add new function QUtil::read_file_into_memory.
+
 2019-06-21  Jay Berkenbilt  <ejb@ql.org>
 
 	* When supported, qpdf builds with -fvisibility=hidden, which

fuzz/standalone_fuzz_target_runner.cc

@@ -1,46 +1,18 @@
 #include <qpdf/QUtil.hh>
-#include <qpdf/PointerHolder.hh>
-#include <qpdf/QIntC.hh>
 #include <iostream>
 #include <string>
 
 extern "C" int LLVMFuzzerTestOneInput(unsigned char const* data, size_t size);
 
-static void read_file_into_memory(
-    char const* filename,
-    PointerHolder<unsigned char>& file_buf, size_t& size)
-{
-    FILE* f = QUtil::safe_fopen(filename, "rb");
-    fseek(f, 0, SEEK_END);
-    size = QIntC::to_size(QUtil::tell(f));
-    fseek(f, 0, SEEK_SET);
-    file_buf = PointerHolder<unsigned char>(true, new unsigned char[size]);
-    unsigned char* buf_p = file_buf.getPointer();
-    size_t bytes_read = 0;
-    size_t len = 0;
-    while ((len = fread(buf_p + bytes_read, 1, size - bytes_read, f)) > 0)
-    {
-        bytes_read += len;
-    }
-    if (bytes_read != size)
-    {
-        throw std::runtime_error(
-            std::string("failure reading file ") + filename +
-            " into memory: read " +
-            QUtil::uint_to_string(bytes_read) + "; wanted " +
-            QUtil::uint_to_string(size));
-    }
-    fclose(f);
-}
-
 int main(int argc, char **argv)
 {
     for (int i = 1; i < argc; i++)
     {
-        PointerHolder<unsigned char> file_buf;
+        PointerHolder<char> file_buf;
         size_t size = 0;
-        read_file_into_memory(argv[i], file_buf, size);
+        QUtil::read_file_into_memory(argv[i], file_buf, size);
-        LLVMFuzzerTestOneInput(file_buf.getPointer(), size);
+        LLVMFuzzerTestOneInput(
+            reinterpret_cast<unsigned char*>(file_buf.getPointer()), size);
         std::cout << argv[i] << " successful" << std::endl;
     }
     return 0;

include/qpdf/QUtil.hh

@@ -24,6 +24,7 @@
 
 #include <qpdf/DLL.h>
 #include <qpdf/Types.h>
+#include <qpdf/PointerHolder.hh>
 #include <string>
 #include <list>
 #include <vector>
@@ -304,6 +305,9 @@ namespace QUtil
     std::list<std::string> read_lines_from_file(char const* filename);
     QPDF_DLL
     std::list<std::string> read_lines_from_file(std::istream&);
+    QPDF_DLL
+    void read_file_into_memory(
+        char const* filename, PointerHolder<char>& file_buf, size_t& size);
 
     // This used to be called strcasecmp, but that is a macro on some
     // platforms, so we have to give it a name that is not likely to

libqpdf/QUtil.cc

@@ -957,6 +957,45 @@ QUtil::read_lines_from_file(char const* filename)
     return lines;
 }
 
+void
+QUtil::read_file_into_memory(
+    char const* filename,
+    PointerHolder<char>& file_buf, size_t& size)
+{
+    FILE* f = safe_fopen(filename, "rb");
+    fseek(f, 0, SEEK_END);
+    size = QIntC::to_size(QUtil::tell(f));
+    fseek(f, 0, SEEK_SET);
+    file_buf = PointerHolder<char>(true, new char[size]);
+    char* buf_p = file_buf.getPointer();
+    size_t bytes_read = 0;
+    size_t len = 0;
+    while ((len = fread(buf_p + bytes_read, 1, size - bytes_read, f)) > 0)
+    {
+        bytes_read += len;
+    }
+    if (bytes_read != size)
+    {
+        if (ferror(f))
+        {
+            throw std::runtime_error(
+                std::string("failure reading file ") + filename +
+                " into memory: read " +
+                uint_to_string(bytes_read) + "; wanted " +
+                uint_to_string(size));
+        }
+        else
+        {
+            throw std::runtime_error(
+                std::string("premature eof reading file ") + filename +
+                " into memory: read " +
+                uint_to_string(bytes_read) + "; wanted " +
+                uint_to_string(size));
+        }
+    }
+    fclose(f);
+}
+
 std::list<std::string>
 QUtil::read_lines_from_file(std::istream& in)
 {

libtests/qutil.cc

@@ -400,7 +400,7 @@ void same_file_test()
     assert_same_file("", "qutil.out", false);
 }
 
-void read_lines_from_file_test()
+void read_from_file_test()
 {
     std::list<std::string> lines = QUtil::read_lines_from_file("other-file");
     for (std::list<std::string>::iterator iter = lines.begin();
@@ -408,6 +408,15 @@ void read_lines_from_file_test()
     {
         std::cout << *iter << std::endl;
     }
+    PointerHolder<char> buf;
+    size_t size = 0;
+    QUtil::read_file_into_memory("other-file", buf, size);
+    std::cout << "read " << size << " bytes" << std::endl;
+    char const* p = buf.getPointer();
+    assert(size == 24652);
+    assert(memcmp(p, "This file is used for qutil testing.", 36) == 0);
+    assert(p[59] == static_cast<char>(13));
+    assert(memcmp(p + 24641, "very long.", 10) == 0);
 }
 
 void assert_hex_encode(std::string const& input, std::string const& expected)
@@ -472,8 +481,8 @@ int main(int argc, char* argv[])
 	get_whoami_test();
 	std::cout << "---- file" << std::endl;
 	same_file_test();
-	std::cout << "---- lines from file" << std::endl;
+	std::cout << "---- read from file" << std::endl;
-	read_lines_from_file_test();
+	read_from_file_test();
 	std::cout << "---- hex encode/decode" << std::endl;
 	hex_encode_decode_test();
     }

qpdf/test_driver.cc

@@ -168,44 +168,6 @@ static void print_rect(std::ostream& out,
         << r.urx << ", " << r.ury << "]";
 }
 
-static void read_file_into_memory(
-    char const* filename,
-    PointerHolder<char>& file_buf, size_t& size)
-{
-    FILE* f = QUtil::safe_fopen(filename, "rb");
-    fseek(f, 0, SEEK_END);
-    size = QIntC::to_size(QUtil::tell(f));
-    fseek(f, 0, SEEK_SET);
-    file_buf = PointerHolder<char>(true, new char[size]);
-    char* buf_p = file_buf.getPointer();
-    size_t bytes_read = 0;
-    size_t len = 0;
-    while ((len = fread(buf_p + bytes_read, 1, size - bytes_read, f)) > 0)
-    {
-        bytes_read += len;
-    }
-    if (bytes_read != size)
-    {
-        if (ferror(f))
-        {
-            throw std::runtime_error(
-                std::string("failure reading file ") + filename +
-                " into memory: read " +
-                QUtil::uint_to_string(bytes_read) + "; wanted " +
-                QUtil::uint_to_string(size));
-        }
-        else
-        {
-            throw std::logic_error(
-                std::string("premature eof reading file ") + filename +
-                " into memory: read " +
-                QUtil::uint_to_string(bytes_read) + "; wanted " +
-                QUtil::uint_to_string(size));
-        }
-    }
-    fclose(f);
-}
-
 #define assert_compare_numbers(expected, expr) \
     compare_numbers(#expr, expected, expr)
 
@@ -277,7 +239,7 @@ void runtest(int n, char const* filename1, char const* arg2)
 
         std::string filename(std::string(filename1) + ".obfuscated");
         size_t size = 0;
-        read_file_into_memory(filename.c_str(), file_buf, size);
+        QUtil::read_file_into_memory(filename.c_str(), file_buf, size);
         char* p = file_buf.getPointer();
         for (size_t i = 0; i < size; ++i)
         {
@@ -308,7 +270,7 @@ void runtest(int n, char const* filename1, char const* arg2)
     {
         QTC::TC("qpdf", "exercise processMemoryFile");
         size_t size = 0;
-        read_file_into_memory(filename1, file_buf, size);
+        QUtil::read_file_into_memory(filename1, file_buf, size);
 	pdf.processMemoryFile(filename1, file_buf.getPointer(), size);
     }