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#include <cerrno>
#include <map>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <dirent.h>
#include <fcntl.h>
#include "references.hh"
#include "hash.hh"
static void search(const string & s,
Strings & ids, Strings & seen)
{
for (Strings::iterator i = ids.begin();
i != ids.end(); )
{
if (s.find(*i) == string::npos)
i++;
else {
debug(format("found reference to `%1%'") % *i);
seen.push_back(*i);
i = ids.erase(i);
}
}
}
void checkPath(const string & path,
Strings & ids, Strings & seen)
{
struct stat st;
if (lstat(path.c_str(), &st))
throw SysError(format("getting attributes of path `%1%'") % path);
if (S_ISDIR(st.st_mode)) {
AutoCloseDir dir = opendir(path.c_str());
struct dirent * dirent;
while (errno = 0, dirent = readdir(dir)) {
string name = dirent->d_name;
if (name == "." || name == "..") continue;
search(name, ids, seen);
checkPath(path + "/" + name, ids, seen);
}
}
else if (S_ISREG(st.st_mode)) {
debug(format("checking `%1%'") % path);
AutoCloseFD fd = open(path.c_str(), O_RDONLY);
if (fd == -1) throw SysError(format("opening file `%1%'") % path);
unsigned char * buf = new unsigned char[st.st_size];
readFull(fd, buf, st.st_size);
search(string((char *) buf, st.st_size), ids, seen);
delete buf; /* !!! autodelete */
}
else if (S_ISLNK(st.st_mode)) {
char buf[st.st_size];
if (readlink(path.c_str(), buf, st.st_size) != st.st_size)
throw SysError(format("reading symbolic link `%1%'") % path);
search(string(buf, st.st_size), ids, seen);
}
else throw Error(format("unknown file type: %1%") % path);
}
Strings filterReferences(const string & path, const Strings & paths)
{
map<string, string> backMap;
Strings ids;
Strings seen;
/* For efficiency (and a higher hit rate), just search for the
hash part of the file name. (This assumes that all references
have the form `HASH-bla'). */
for (Strings::const_iterator i = paths.begin();
i != paths.end(); i++)
{
string s = string(baseNameOf(*i), 0, 32);
parseHash(s);
ids.push_back(s);
backMap[s] = *i;
}
checkPath(path, ids, seen);
Strings found;
for (Strings::iterator i = seen.begin(); i != seen.end(); i++)
{
map<string, string>::iterator j;
if ((j = backMap.find(*i)) == backMap.end()) abort();
found.push_back(j->second);
}
return found;
}
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