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diff --git a/man/man3/fcall.html b/man/man3/fcall.html new file mode 100644 index 00000000..926b47dc --- /dev/null +++ b/man/man3/fcall.html @@ -0,0 +1,274 @@ +<head> +<title>fcall(3) - Plan 9 from User Space</title> +<meta content="text/html; charset=utf-8" http-equiv=Content-Type> +</head> +<body bgcolor=#ffffff> +<table border=0 cellpadding=0 cellspacing=0 width=100%> +<tr height=10><td> +<tr><td width=20><td> +<tr><td width=20><td><b>FCALL(3)</b><td align=right><b>FCALL(3)</b> +<tr><td width=20><td colspan=2> + <br> +<p><font size=+1><b>NAME </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Fcall, convS2M, convD2M, convM2S, convM2D, fcallfmt, dirfmt, dirmodefmt, + read9pmsg, statcheck, sizeS2M, sizeD2M – interface to Plan 9 File + protocol<br> + +</table> +<p><font size=+1><b>SYNOPSIS </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <tt><font size=+1>#include <u.h><br> + #include <libc.h><br> + #include <fcall.h> + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>uint convS2M(Fcall *f, uchar *ap, uint nap) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>uint convD2M(Dir *d, uchar *ap, uint nap) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>uint convM2S(uchar *ap, uint nap, Fcall *f) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>uint convM2D(uchar *ap, uint nap, Dir *d, char *strs) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>int dirfmt(Fmt*) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>int fcallfmt(Fmt*) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>int dirmodefmt(Fmt*) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>int read9pmsg(int fd, uchar *buf, uint nbuf) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>int statcheck(uchar *buf, uint nbuf) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>uint sizeS2M(Fcall *f) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>uint sizeD2M(Dir *d)<br> + </font></tt> +</table> +<p><font size=+1><b>DESCRIPTION </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + These routines convert messages in the machine-independent format + of the Plan 9 file protocol, 9P, to and from a more convenient + form, an <tt><font size=+1>Fcall</font></tt> structure: + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <tt><font size=+1>#define MAXWELEM 16<br> + typedef<br> + struct Fcall<br> + {<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + uchar type;<br> + u32int fid;<br> + ushort tag;<br> + union {<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + struct {<br> + u32int msize; /* Tversion, Rversion */<br> + char *version; /* Tversion, Rversion */<br> + };<br> + struct {<br> + ushort oldtag; /* Tflush */<br> + };<br> + struct {<br> + char *ename; /* Rerror */<br> + };<br> + struct {<br> + Qid qid; /* Rattach, Ropen, Rcreate */<br> + u32int iounit; /* Ropen, Rcreate */<br> + };<br> + struct {<br> + Qid aqid; /* Rauth */<br> + };<br> + struct {<br> + u32int afid; /* Tauth, Tattach */<br> + char *uname; /* Tauth, Tattach */<br> + char *aname; /* Tauth, Tattach */<br> + };<br> + struct {<br> + u32int perm; /* Tcreate */ <br> + char *name; /* Tcreate */<br> + uchar mode; /* Tcreate, Topen */<br> + };<br> + struct {<br> + u32int newfid; /* Twalk */<br> + ushort nwname; /* Twalk */<br> + char *wname[MAXWELEM]; /* Twalk */<br> + };<br> + struct {<br> + ushort nwqid; /* Rwalk */<br> + Qid wqid[MAXWELEM]; /* Rwalk */<br> + };<br> + struct {<br> + vlong offset; /* Tread, Twrite */<br> + u32int count; /* Tread, Twrite, Rread */<br> + char *data; /* Twrite, Rread */<br> + };<br> + struct {<br> + ushort nstat; /* Twstat, Rstat */<br> + uchar *stat; /* Twstat, Rstat */<br> + };<br> + + </table> + };<br> + + </table> + } Fcall;<br> + /* these are implemented as macros */<br> + uchar GBIT8(uchar*)<br> + ushort GBIT16(uchar*)<br> + ulong GBIT32(uchar*)<br> + vlong GBIT64(uchar*)<br> + void PBIT8(uchar*, uchar)<br> + void PBIT16(uchar*, ushort)<br> + void PBIT32(uchar*, ulong)<br> + void PBIT64(uchar*, vlong)<br> + #define BIT8SZ 1<br> + #define BIT16SZ 2<br> + #define BIT32SZ 4<br> + #define BIT64SZ 8<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + This structure is defined in <tt><font size=+1><fcall.h></font></tt>. See section 5 for a full + description of 9P messages and their encoding. For all message + types, the <tt><font size=+1>type</font></tt> field of an <tt><font size=+1>Fcall</font></tt> holds one of <tt><font size=+1>Tversion</font></tt>, <tt><font size=+1>Rversion</font></tt>, + <tt><font size=+1>Tattach</font></tt>, <tt><font size=+1>Rattach</font></tt>, etc. (defined in an enumerated type in <tt><font size=+1><fcall.h></font></tt>). + <tt><font size=+1>Fid</font></tt> is used by most messages, and + <tt><font size=+1>tag</font></tt> is used by all messages. The other fields are used selectively + by the message types given in comments. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>ConvM2S</i> takes a 9P message at <i>ap</i> of length <i>nap</i>, and uses it to + fill in <tt><font size=+1>Fcall</font></tt> structure <i>f</i>. If the passed message including any + data for <tt><font size=+1>Twrite</font></tt> and <tt><font size=+1>Rread</font></tt> messages is formatted properly, the + return value is the number of bytes the message occupied in the + buffer <i>ap</i>, which will always be less than or equal to <i>nap</i>; + otherwise it is 0. For <tt><font size=+1>Twrite</font></tt> and <tt><font size=+1>Tread</font></tt> messages, <tt><font size=+1>data</font></tt> is set + to a pointer into the argument message, not a copy. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>ConvS2M</i> does the reverse conversion, turning <i>f</i> into a message + starting at <i>ap</i>. The length of the resulting message is returned. + For <tt><font size=+1>Twrite</font></tt> and <tt><font size=+1>Rread</font></tt> messages, <tt><font size=+1>count</font></tt> bytes starting at <tt><font size=+1>data</font></tt> are + copied into the message. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + The constant <tt><font size=+1>IOHDRSZ</font></tt> is a suitable amount of buffer to reserve + for storing the 9P header; the data portion of a <tt><font size=+1>Twrite</font></tt> or <tt><font size=+1>Rread</font></tt> + will be no more than the buffer size negotiated in the <tt><font size=+1>Tversion/Rversion</font></tt> + exchange, minus <tt><font size=+1>IOHDRSZ</font></tt>. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + The routine <i>sizeS2M</i> returns the number of bytes required to store + the machine-independent representation of the <tt><font size=+1>Fcall</font></tt> structure + <i>f</i>, including its initial 32-bit size field. In other words, it + reports the number of bytes produced by a successful call to <i>convS2M</i>. + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + Another structure is <tt><font size=+1>Dir</font></tt>, used by the routines described in <a href="../man3/stat.html"><i>stat</i>(3)</a>. + <i>ConvM2D</i> converts the machine-independent form starting at <i>ap</i> into + <i>d</i> and returns the length of the machine-independent encoding. + The strings in the returned <tt><font size=+1>Dir</font></tt> structure are stored at successive + locations starting at <tt><font size=+1>strs</font></tt>. Usually <tt><font size=+1>strs</font></tt> will + point to storage immediately after the <tt><font size=+1>Dir</font></tt> itself. It can also + be a <tt><font size=+1>nil</font></tt> pointer, in which case the string pointers in the returned + <tt><font size=+1>Dir</font></tt> are all <tt><font size=+1>nil</font></tt>; however, the return value still includes their + length. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>ConvD2M</i> does the reverse translation, also returning the length + of the encoding. If the buffer is too short, the return value + will be <tt><font size=+1>BIT16SZ</font></tt> and the correct size will be returned in the first + <tt><font size=+1>BIT16SZ</font></tt> bytes. (If the buffer is less that <tt><font size=+1>BIT16SZ</font></tt>, the return + value is zero; therefore a correct test for complete packing of + the + message is that the return value is greater than <tt><font size=+1>BIT16SZ</font></tt>). The + macro <tt><font size=+1>GBIT16</font></tt> can be used to extract the correct value. The related + macros with different sizes retrieve the corresponding-sized quantities. + <tt><font size=+1>PBIT16</font></tt> and its brethren place values in messages. With the exception + of handling short buffers in <i>convD2M</i>, + these macros are not usually needed except by internal routines. + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + Analogous to <i>sizeS2M</i>, <i>sizeD2M</i> returns the number of bytes required + to store the machine-independent representation of the <tt><font size=+1>Dir</font></tt> structure + <i>d</i>, including its initial 16-bit size field. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + The routine <tt><font size=+1>statcheck</font></tt> checks whether the <i>nbuf</i> bytes of <i>buf</i> contain + a validly formatted machine-independent <tt><font size=+1>Dir</font></tt> entry suitable as + an argument, for example, for the <tt><font size=+1>wstat</font></tt> (see <a href="../man3/stat.html"><i>stat</i>(3)</a>) system call. + It checks that the sizes of all the elements of the the entry + sum to exactly <i>nbuf</i>, which is a simple but effective test + of validity. <i>Nbuf</i> and <i>buf</i> should include the second two-byte (16-bit) + length field that precedes the entry when formatted in a 9P message + (see <i>stat</i>(9p)); in other words, <i>nbuf</i> is 2 plus the sum of the + sizes of the entry itself. <i>Statcheck</i> also verifies that the length + field has the correct value (that is, <i>nbuf</i><tt><font size=+1>−2</font></tt>). It returns <tt><font size=+1>0 + </font></tt>for a valid entry and <tt><font size=+1>−1</font></tt> for an incorrectly formatted entry. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>Dirfmt</i>, <i>fcallfmt</i>, and <i>dirmodefmt</i> are formatting routines, suitable + for <a href="../man3/fmtinstall.html"><i>fmtinstall</i>(3)</a>. They convert <tt><font size=+1>Dir*</font></tt>, <tt><font size=+1>Fcall*</font></tt>, and <tt><font size=+1>long</font></tt> values + into string representations of the directory buffer, <tt><font size=+1>Fcall</font></tt> buffer, + or file mode value. <i>Fcallfmt</i> assumes that <i>dirfmt</i> has been installed + with format letter <tt><font size=+1>D</font></tt> and <i>dirmodefmt</i> with format + letter <tt><font size=+1>M</font></tt>. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>Read9pmsg</i> calls <a href="../man3/read.html"><i>read</i>(3)</a> multiple times, if necessary, to read + an entire 9P message into <tt><font size=+1>buf</font></tt>. The return value is 0 for end of + file, or -1 for error; it does not return partial messages.<br> + +</table> +<p><font size=+1><b>SOURCE </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <tt><font size=+1>/usr/local/plan9/src/lib9<br> + </font></tt> +</table> +<p><font size=+1><b>SEE ALSO </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <a href="../man3/intro.html"><i>intro</i>(3)</a>, <a href="../man3/9p.html"><i>9p</i>(3)</a>, <a href="../man3/stat.html"><i>stat</i>(3)</a>, <i>intro</i>(9p)<br> + +</table> + +<td width=20> +<tr height=20><td> +</table> +<!-- TRAILER --> +<table border=0 cellpadding=0 cellspacing=0 width=100%> +<tr height=15><td width=10><td><td width=10> +<tr><td><td> +<center> +<a href="../../"><img src="../../dist/spaceglenda100.png" alt="Space Glenda" border=1></a> +</center> +</table> +<!-- TRAILER --> +</body></html> |