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#include "cmdline.h"
#include "images.h"
#include "printdata.h"
#include <fstream>
using namespace std;
using namespace mysqlpp;
// This is just an implementation detail for the example. Skip down to
// main() for the concept this example is trying to demonstrate. You
// can simply assume that, given a BLOB containing a valid JPEG, it
// returns true.
static bool
is_jpeg(const mysqlpp::sql_blob& img, const char** whynot)
{
// See http://stackoverflow.com/questions/2253404/ for
// justification for the various tests.
const unsigned char* idp =
reinterpret_cast<const unsigned char*>(img.data());
if (img.size() < 125) {
*whynot = "a valid JPEG must be at least 125 bytes";
}
else if ((idp[0] != 0xFF) || (idp[1] != 0xD8)) {
*whynot = "file does not begin with JPEG sigil bytes";
}
else if ((memcmp(idp + 6, "JFIF", 4) != 0) &&
(memcmp(idp + 6, "Exif", 4) != 0)) {
*whynot = "file does not contain JPEG type word";
}
else {
*whynot = 0;
return true;
}
return false;
}
// Skip to main() before studying this. This is a little too
// low-level to bother with on your first pass thru the code.
static bool
load_jpeg_file(const mysqlpp::examples::CommandLine& cmdline,
images& img, string& img_name)
{
if (cmdline.extra_args().size() == 0) {
// Nothing for us to do here. Caller will insert NULL BLOB.
return true;
}
// Got a file's name on the command line, so open it.
img_name = cmdline.extra_args()[0];
ifstream img_file(img_name.c_str(), ios::binary);
if (img_file) {
// Slurp file contents into RAM with minimum copying. (Idiom
// explained here: http://stackoverflow.com/questions/116038/)
//
// By loading the file into a C++ string (stringstream::str())
// and assigning that directly to a mysqlpp::sql_blob, we avoid
// truncating the binary data at the first null character.
img.data.data = static_cast<const stringstream*>(
&(stringstream() << img_file.rdbuf()))->str();
// Check JPEG data for sanity.
const char* error;
if (is_jpeg(img.data.data, &error)) {
return true;
}
else {
cerr << '"' << img_name << "\" isn't a JPEG: " <<
error << '!' << endl;
}
}
cmdline.print_usage("[jpeg_file]");
return false;
}
int
main(int argc, char *argv[])
{
// Get database access parameters from command line
mysqlpp::examples::CommandLine cmdline(argc, argv);
if (!cmdline) {
return 1;
}
try {
// Establish the connection to the database server.
mysqlpp::Connection con(mysqlpp::examples::db_name,
cmdline.server(), cmdline.user(), cmdline.pass());
// Load the file named on the command line
images img(mysqlpp::null, mysqlpp::null);
string img_name("NULL");
if (load_jpeg_file(cmdline, img, img_name)) {
// Insert image data or SQL NULL into the images.data BLOB
// column. The key here is that we're holding the raw
// binary data in a mysqlpp::sql_blob, which avoids data
// conversion problems that can lead to treating BLOB data
// as C strings, thus causing null-truncation. The fact
// that we're using SSQLS here is a side issue, simply
// demonstrating that mysqlpp::Null<mysqlpp::sql_blob> is
// now legal in SSQLS, as of MySQL++ 3.0.7.
Query query = con.query();
query.insert(img);
SimpleResult res = query.execute();
// Report successful insertion
cout << "Inserted \"" << img_name <<
"\" into images table, " << img.data.data.size() <<
" bytes, ID " << res.insert_id() << endl;
}
}
catch (const BadQuery& er) {
// Handle any query errors
cerr << "Query error: " << er.what() << endl;
return -1;
}
catch (const BadConversion& er) {
// Handle bad conversions
cerr << "Conversion error: " << er.what() << endl <<
"\tretrieved data size: " << er.retrieved <<
", actual size: " << er.actual_size << endl;
return -1;
}
catch (const Exception& er) {
// Catch-all for any other MySQL++ exceptions
cerr << "Error: " << er.what() << endl;
return -1;
}
return 0;
}
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