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There are three functions available: <PRE> int cl_loaddb(const char *filename, struct cl_node **root, int *virnum); int cl_loaddbdir(const char *dirname, struct cl_node **root, int *virnum); char *cl_retdbdir(void); </PRE> <I>cl_loaddb()</I> loads a particular database, <I>cl_loaddbdir()</I> loads all <I>.cvd</I> (and older <I>.db</I>, .db2) databases from a directory <I>dirname</I>. <I>cl_retdbdir()</I> returns a hardcoded database directory path. Initial internal database (Aho-Corasick tree, trie; see <A HREF="node47.html#engine">6.3</A>) will be saved under <I>root</I> and a number of signatures loaded will be <B>added</B> <A NAME="tex2html56" HREF="footnode.html#foot537"><SUP>7</SUP></A> to <I>virnum</I>. Pointer to the trie must initially point to NULL. If you don't care about number of signatures pass NULL as a third argument. <I>cl_loaddb</I> functions return 0 on success and other value on failure. <PRE> struct cl_node *root = NULL; int ret; ret = cl_loaddbdir(cl_retdbdir(), &root, NULL); </PRE> There's an elegant way to print libclamav's error codes: <PRE> char *cl_strerror(int clerror); </PRE> <I>cl_strerror()</I> returns a (statically allocated) string describing a <I>clerror</I> code: <PRE> if(ret) { printf("cl_loaddbdir() error: %s\n", cl_strerror(ret)); exit(1); } </PRE> When database is loaded you must build the final trie with: <PRE> void cl_buildtrie(struct cl_node *root); </PRE> In our example: <PRE> cl_buildtrie(root); </PRE> OK, now you can scan a buffer, a descriptor or a file with: <PRE> int cl_scanbuff(const char *buffer, unsigned int length, char **virname, const struct cl_node *root); int cl_scandesc(int desc, char **virname, unsigned long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options); int cl_scanfile(const char *filename, char **virname, unsigned long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options); </PRE> All the functions save a virus name address under <I>virname</I> pointer. <I>virname</I> points to a name in the trie structure thus it can't be released directly. <I>cl_scandesc()</I> and <I>cl_scanfile()</I> can increase the <I>scanned</I> value in CL_COUNT_PRECISION units, they also support archive limits: <PRE> struct cl_limits { int maxreclevel; int maxfiles; long int maxfilesize; }; </PRE> The last argument configures scan engine. Currently it supports <B>CL_ARCHIVE</B> (enables archive scanning), <B>CL_RAW</B> (disables archive scanning) and <B>CL_MAIL</B> (enables mbox and Maildir scanning) and <B>CL_DISABLERAR</B> (disables the built-in RAR unpacker which leaks like hell). These functions return 0 (<B>CL_CLEAN</B>) when no virus is found, <B>CL_VIRUS</B> when virus is found and other value on failure. <PRE> struct cl_limits limits; char *virname; memset(&limits, 0, sizeof(struct cl_limits)); /* maximal number of files in archive */; limits.maxfiles = 1000 /* maximal archived file size == 10 MB */ limits.maxfilesize = 10 * 1048576; /* maximal recursion level */ limits.maxreclevel = 5; if((ret = cl_scanfile("/home/zolw/test", &virname, NULL, root, &limits, CL_ARCHIVE)) == CL_VIRUS) { printf("Detected %s virus.\n", virname); } else { printf("No virus detected.\n"); if(ret != CL_CLEAN) printf("Error: %s\n", cl_strerror(ret)); } </PRE> Release the trie if you no longer need it: <PRE> void cl_freetrie(struct cl_node *root); </PRE> You will find an example scanner in clamav sources (/example). Program based on libclamav must be linked against it: <PRE> gcc -Wall ex1.c -o ex1 -lclamav </PRE> Enjoy ! <P> <HR> <!--Navigation Panel--> <A NAME="tex2html757" HREF="node46.html"> <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="/usr/share/latex2html/icons/next.png"></A> <A NAME="tex2html753" HREF="node44.html"> <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="/usr/share/latex2html/icons/up.png"></A> <A NAME="tex2html747" HREF="node44.html"> <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="/usr/share/latex2html/icons/prev.png"></A> <A NAME="tex2html755" HREF="node1.html"> <IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents" SRC="/usr/share/latex2html/icons/contents.png"></A> <BR> <B> Next:</B> <A NAME="tex2html758" HREF="node46.html">Database reloading</A> <B> Up:</B> <A NAME="tex2html754" HREF="node44.html">LibClamAV</A> <B> Previous:</B> <A NAME="tex2html748" HREF="node44.html">LibClamAV</A>   <B> <A NAME="tex2html756" HREF="node1.html">Contents</A></B> <!--End of Navigation Panel--> <ADDRESS> Tomasz Kojm 2004-02-11 </ADDRESS> </BODY> </HTML>