1 1.1 glass m4 - macro processor 2 1.1 glass 3 1.1 glass PD m4 is based on the macro tool distributed with the software 4 1.1 glass tools (VOS) package, and described in the "SOFTWARE TOOLS" and 5 1.1 glass "SOFTWARE TOOLS IN PASCAL" books. It has been expanded to include 6 1.1 glass most of the command set of SysV m4, the standard UN*X macro processor. 7 1.1 glass 8 1.1 glass Since both PD m4 and UN*X m4 are based on SOFTWARE TOOLS macro, 9 1.1 glass there may be certain implementation similarities between 10 1.1 glass the two. The PD m4 was produced without ANY references to m4 11 1.1 glass sources. 12 1.1 glass 13 1.1 glass written by: Ozan S. Yigit 14 1.1 glass 15 1.1 glass References: 16 1.1 glass 17 1.1 glass Software Tools distribution: macro 18 1.1 glass 19 1.1 glass Kernighan, Brian W. and P. J. Plauger, SOFTWARE 20 1.1 glass TOOLS IN PASCAL, Addison-Wesley, Mass. 1981 21 1.1 glass 22 1.1 glass Kernighan, Brian W. and P. J. Plauger, SOFTWARE 23 1.1 glass TOOLS, Addison-Wesley, Mass. 1976 24 1.1 glass 25 1.1 glass Kernighan, Brian W. and Dennis M. Ritchie, 26 1.1 glass THE M4 MACRO PROCESSOR, Unix Programmer's Manual, 27 1.1 glass Seventh Edition, Vol. 2, Bell Telephone Labs, 1979 28 1.1 glass 29 1.1 glass System V man page for M4 30 1.1 glass 31 1.1 glass 32 1.1 glass Implementation Notes: 33 1.1 glass 34 1.1 glass [1] PD m4 uses a different (and simpler) stack mechanism than the one 35 1.1 glass described in Software Tools and Software Tools in Pascal books. 36 1.1 glass The triple stack thing is replaced with a single stack containing 37 1.1 glass the call frames and the arguments. Each frame is back-linked to a 38 1.1 glass previous stack frame, which enables us to rewind the stack after 39 1.1 glass each nested call is completed. Each argument is a character pointer 40 1.1 glass to the beginning of the argument string within the string space. 41 1.1 glass The only exceptions to this are (*) arg 0 and arg 1, which are 42 1.1 glass the macro definition and macro name strings, stored dynamically 43 1.1 glass for the hash table. 44 1.1 glass 45 1.1 glass . . 46 1.1 glass | . | <-- sp | . | 47 1.1 glass +-------+ +-----+ 48 1.1 glass | arg 3 ------------------------------->| str | 49 1.1 glass +-------+ | . | 50 1.1 glass | arg 2 --------------+ . 51 1.1 glass +-------+ | 52 1.1 glass * | | | 53 1.1 glass +-------+ | +-----+ 54 1.1 glass | plev | <-- fp +---------------->| str | 55 1.1 glass +-------+ | . | 56 1.1 glass | type | . 57 1.1 glass +-------+ 58 1.1 glass | prcf -----------+ plev: paren level 59 1.1 glass +-------+ | type: call type 60 1.1 glass | . | | prcf: prev. call frame 61 1.1 glass . | 62 1.1 glass +-------+ | 63 1.1 glass | <----------+ 64 1.1 glass +-------+ 65