introducing iii-extract-riff-chunk utility

for getting the timestamp out of Nikon AVIs

Signed-off-by: Michael Krelin <hacker@klever.net>

3 files changed, 251 insertions, 0 deletions

diff --git a/src/.gitignore b/src/.gitignore
index 425033a..f1c5466 100644
--- a/src/.gitignore
+++ b/src/.gitignore
@@ -9,2 +9,3 @@ soapeyefiService.h
 /iiid
 /COPYING.cc
+/iii-extract-riff-chunk
diff --git a/src/Makefile.am b/src/Makefile.am
index b5b7d5c..b31bed5 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1,2 +1,3 @@
+bin_PROGRAMS=iii-extract-riff-chunk
 sbin_PROGRAMS=iiid
 noinst_HEADERS = \
@@ -18,4 +19,7 @@ nodist_iiid_SOURCES = \
 iiid_LDADD = ${MODULES_LIBS} ${UUID_LIBS}
 
+iii_extract_riff_chunk_SOURCES = iii-extract-riff-chunk.cc
+nodist_iii_extract_riff_chunk_SOURCES = COPYING.cc
+
 COPYING.cc: ${top_srcdir}/COPYING
         echo "const char * COPYING = " >$@ || (rm $@;exit 1)
diff --git a/src/iii-extract-riff-chunk.cc b/src/iii-extract-riff-chunk.cc
new file mode 100644
index 0000000..3a06db2
--- a/dev/null
+++ b/src/iii-extract-riff-chunk.cc
@@ -0,0 +1,246 @@
+/* vim:set sw=8 nosi noai cin cino=:0,l1,g0: */
+#include <stdint.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <cstring>
+#include <iostream>
+#include <fstream>
+#include <stdexcept>
+#include <cassert>
+#include <list>
+#include <string>
+#include <iterator>
+
+#include "config.h"
+
+#define PHEADER \
+        PACKAGE " Version " VERSION "\n" \
+        "Copyright (c) 2009-2010 Klever Group"
+
+typedef uint32_t fourcc_type;
+enum fourcc_value {
+        fourcc_RIFF = 0x46464952, fourcc_AVI  = 0x20495641, fourcc_LIST = 0x5453494c,
+        fourcc_hdrl = 0x6c726468, fourcc_strl = 0x6c727473,
+        fourcc_ncdt = 0x7464636e, fourcc_ncvr = 0x7276636e, fourcc_nctg = 0x6774636e, fourcc_ncth = 0x6874636e
+};
+
+fourcc_type str2fourcc(const char *str) {
+        fourcc_type rv = 0;
+        return *(fourcc_type*)strncpy((char*)&rv,str,sizeof(rv));
+}
+const std::string fourcc2str(fourcc_type fcc) {
+        char rv[sizeof(fcc)+1];
+        *(fourcc_type*)rv = fcc;
+        rv[sizeof(fcc)]=0;
+        return rv;
+}
+
+#pragma pack(1)
+struct riff_sized_head {
+        fourcc_type fourcc;
+        uint32_t size;
+};
+#pragma pack()
+
+class exceptional_success : public std::exception { };
+
+struct riff {
+        struct chunk_type {
+                riff_sized_head head;
+                uint32_t left;
+
+                chunk_type(riff& r) {
+                        r.read(&head);
+                        left = head.size;
+                }
+        };
+
+        std::istream *in;
+        typedef std::list<chunk_type> chunks_type;
+        chunks_type chunks;
+
+        riff(std::istream& i) : in(&i) { }
+
+        protected:
+
+        int begin_chunk() {
+                chunks.push_back( chunk_type(*this) );
+                return chunks.size();
+        }
+        void end_chunk(int level) {
+                assert(in); assert(chunks.size()==level);
+                std::streamsize o = chunks.back().left;
+                chunks.pop_back();
+                if(!o) return;
+                in->seekg(o,std::ios::cur);
+                for(chunks_type::iterator i=chunks.begin(),ie=chunks.end() ;i!=ie; (i++)->left -= o) ;
+        }
+
+        void read(void *p,size_t n) {
+                assert(in);
+                if( (!chunks.empty()) && chunks.back().left < n)
+                        throw std::runtime_error("attempt to read beyond the end of chunk");
+                if(!in->read((char*)p,n))
+                        throw std::runtime_error("failed to read()");
+                std::streamsize gc = in->gcount();
+                for(chunks_type::iterator i=chunks.begin(),ie=chunks.end();i!=ie;++i) {
+                        i->left -= gc; assert(i->left >= 0);
+                }
+                if(gc!=n) throw std::runtime_error("incomplete read()");
+        }
+
+        template<typename T> void read(T* v) { read(v,sizeof(*v)); }
+
+        friend class scoped_chunk;
+
+};
+
+struct scoped_chunk {
+        riff& rs;
+        int level;
+        riff::chunks_type::reverse_iterator chunk_iterator;
+
+        scoped_chunk(riff& rs_) : rs(rs_), level(rs.begin_chunk()), chunk_iterator(rs.chunks.rbegin()) { }
+        ~scoped_chunk() { rs.end_chunk(level); }
+
+        riff::chunk_type& chunk() { return *chunk_iterator; }
+
+        fourcc_type get_chunk_id() { return chunk().head.fourcc; }
+        bool has(uint32_t bytes=1) { return chunk().left >= bytes; }
+
+        template<typename T> T read() { T rv; rs.read(&rv); return rv; }
+        template<typename T> void read(T& t) { rs.read(&t); }
+        void read(void *p,size_t n) { rs.read(p,n); }
+
+};
+
+struct chunk_path_type : public std::list<std::string> {
+
+        chunk_path_type() { }
+        chunk_path_type(const char *str) {
+        for(const char *p0=str,*p1=strchr(p0,'/');p0;p1=p1?strchr(p0=++p1,'/'):(p0=0))
+                if(p0!=p1)
+                        push_back( p1? std::string(p0,p1-p0) : std::string(p0) );
+        }
+
+};
+
+struct chunk_walker {
+        riff& r;
+        chunk_path_type path;
+
+        chunk_walker(riff& r_) : r(r_) { }
+
+        void shoot(scoped_chunk& chunk) {
+                riff::chunk_type& c = chunk.chunk();
+                while(c.left) {
+                        static char tmp[512];
+                        int r = (c.left<sizeof(tmp)) ? c.left : sizeof(tmp) ;
+                        chunk.read(tmp,r); std::cout.write(tmp,r);
+                }
+                if(first) throw exceptional_success();
+        }
+
+        void walk_chunks() {
+                scoped_chunk chunk(r);
+                std::string pc = fourcc2str(chunk.get_chunk_id());
+                bool list = false;
+                switch(chunk.get_chunk_id()) {
+                case fourcc_RIFF: case fourcc_LIST:
+                        list = true;
+                        pc += '.'; pc += fourcc2str(chunk.read<fourcc_type>());
+                        break;
+                }
+                path.push_back(pc);
+                std::pair<chunk_path_type::const_iterator,chunk_path_type::const_iterator>
+                        mm = std::mismatch(path.begin(),path.end(),target.begin());
+                bool dive = list;
+                if(mm.first==path.end()) {
+                        if(mm.second==target.end()) {
+                                shoot(chunk);
+                                dive = false;
+                        }
+                }else{
+                        assert(mm.second!=target.end());
+                        dive = false;
+                }
+
+                if(dive) while(chunk.has()) walk_chunks();
+                path.pop_back();
+        }
+
+
+        chunk_path_type target;
+        chunk_walker& set_target(chunk_path_type t) { target = t; return *this; }
+        bool first;
+        chunk_walker& set_oneshot(bool os) { first = true; return *this; }
+};
+
+void usage(char **argv) {
+        std::cerr << PHEADER << std::endl << std::endl
+                << ' ' << argv[0] << " [options] <avi-file> <chunk-path>" << std::endl
+                << std::endl <<
+                " -h, --help,\n"
+                " --usage        display this text\n"
+                " -V, --version  display version information\n"
+                " -L, --license  show license\n"
+                "\n"
+                "Example: " << argv[0] << " DSC_0001.AVI '/RIFF.AVI /LIST.ncdt/nctg' \\\n"
+                "\t\t| dd bs=1 skip=82 count=19 2>/dev/null\n"
+                "Output:  YYYY:MM:DD HH:MM:SS (for Nikon-recorded AVI)"
+                << std::endl << std::endl;
+        exit(0);
+}
+
+int main(int argc,char **argv) try {
+
+        bool first = false;
+
+        for(;;) {
+                static struct option opts[] = {
+                        { "first", no_argument, 0, '1' },
+                        { "help", no_argument, 0, 'h' },
+                        { "usage", no_argument, 0, 'h' },
+                        { "version", no_argument, 0, 'V' },
+                        { "license", no_argument, 0, 'L' },
+                        { NULL, 0, 0, 0 }
+                };
+                int c = getopt_long(argc,argv,"1hVL",opts,NULL);
+                if(c==-1) break;
+                switch(c) {
+                case 'h':
+                        usage(argv); break;
+                case 'V':
+                        std::cerr << VERSION << std::endl;
+                        exit(0); break;
+                case 'L':
+                        extern const char *COPYING;
+                        std::cerr << COPYING << std::endl;
+                        exit(0); break;
+                case '1':
+                        first = true; break;
+                default:
+                        std::cerr << "Huh?" << std::endl;
+                        exit(1); break;
+                }
+        }
+
+        if(optind!=(argc-2)) usage(argv);
+
+        std::ifstream i(argv[optind],std::ios::in);
+        if(!i) {
+                std::cerr << "Failed to open file '" << argv[optind] << "'" << std::endl;
+                exit(1);
+        }
+        riff rs(i);
+        chunk_walker(rs)
+                .set_target(chunk_path_type(argv[++optind]))
+                .set_oneshot(first)
+                .walk_chunks();
+        return 0;
+}catch(exceptional_success&) {
+        return 0;
+}catch(std::exception &e) {
+        std::cerr << "oops: " << e.what() << std::endl;
+        return 1;
+}