1 static char Sccsid[] = "@(#)fatal.c 1.2 02/15/87"; 2 3 # include "../hdr/macros.h" 4 # include "../hdr/fatal.h" 5 6 /* 7 General purpose error handler. 8 Typically, low level subroutines which detect error conditions 9 (an open or create routine, for example) return the 10 value of calling fatal with an appropriate error message string. 11 E.g., return(fatal("can't do it")); 12 Higher level routines control the execution of fatal 13 via the global word Fflags. 14 The macros FSAVE and FRSTR in <fatal.h> can be used by higher 15 level subroutines to save and restore the Fflags word. 16 17 The argument to fatal is a pointer to an error message string. 18 The action of this routine is driven completely from 19 the "Fflags" global word (see <fatal.h>). 20 The following discusses the interpretation of the various bits 21 of Fflags. 22 23 The FTLMSG bit controls the writing of the error 24 message on file descriptor 2. The message is preceded 25 by the string "ERROR: ", unless the global character pointer 26 "Ffile" is non-zero, in which case the message is preceded 27 by the string "ERROR [<Ffile>]: ". A newline is written 28 after the user supplied message. 29 30 If the FTLCLN bit is on, clean_up is called with an 31 argument of 0 (see clean.c). 32 33 If the FTLFUNC bit is on, the function pointed to by the global 34 function pointer "Ffunc" is called with the user supplied 35 error message pointer as argument. 36 (This feature can be used to log error messages). 37 38 The FTLACT bits determine how fatal should return. 39 If the FTLJMP bit is on longjmp(Fjmp) is 40 called (Fjmp is a global vector of 10 words, see 41 setjmp, longjmp documentation). 42 43 If the FTLEXIT bit is on the value of userexit(1) is 44 passed as an argument to exit(II) 45 (see userexit.c). 46 47 If none of the FTLACT bits are on 48 (the default value for Fflags is 0), the global word 49 "Fvalue" (initialized to -1) is returned. 50 51 If all fatal globals have their default values, fatal simply 52 returns -1. 53 */ 54 55 int Fcnt; 56 int Fflags; 57 char *Ffile; 58 int Fvalue = -1; 59 int (*Ffunc)(); 60 int Fjmp[10]; 61 62 63 fatal(msg) 64 char *msg; 65 { 66 ++Fcnt; 67 if (Fflags & FTLMSG) { 68 syswrite(2,"ERROR",5); 69 if (Ffile) { 70 syswrite(2," [",2); 71 syswrite(2,Ffile,length(Ffile)); 72 syswrite(2,"]",1); 73 } 74 syswrite(2,": ",2); 75 syswrite(2,msg,length(msg)); 76 syswrite(2,"\n",1); 77 } 78 if (Fflags & FTLCLN) 79 clean_up(0); 80 if (Fflags & FTLFUNC) 81 (*Ffunc)(msg); 82 switch (Fflags & FTLACT) { 83 case FTLJMP: 84 longjmp(Fjmp, 1); 85 case FTLEXIT: 86 exit(userexit(1)); 87 case FTLRET: 88 return(Fvalue); 89 } 90 } 91