diff options
Diffstat (limited to 'menudriver.c')
| -rw-r--r-- | menudriver.c | 320 |
1 files changed, 320 insertions, 0 deletions
diff --git a/menudriver.c b/menudriver.c new file mode 100644 index 0000000..0a0847b --- /dev/null +++ b/menudriver.c @@ -0,0 +1,320 @@ +/* general purpose menu driver */ +/* alternatively there is an equivalent shell script, menudriver.sh */ + +/************************************************************************** + * Copyright (C) Research Software Limited 1985-90. All rights reserved. * + * The Miranda system is distributed as free software under the terms in * + * the file "COPYING" which is included in the distribution. * + * * + * Revised to C11 standard and made 64bit compatible, January 2020 * + *------------------------------------------------------------------------*/ + +#include <stdio.h> +#include <stdlib.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <unistd.h> +#include <sys/wait.h> +#include <signal.h> +typedef void (*sighandler)(); +#define pnlim 1024 +struct stat buf; + +char *menuviewer; +char *viewer="less"; +/* +#ifdef UWIN + "more -ne"; +#else + "more -d"; +#endif */ + +#define VIEWERPAUSESATEND . +/* this modifies default behaviour of menudriver to return straight to menu + after displaying section, to avoid two layers of prompt; + choice can be overriden by environment variable RETURNTOMENU=YES/NO */ + +#ifdef VIEWERPAUSESATEND +int fastback=1; +#else +int fastback=0; +#endif + +void callshell(char[]); +void clrscr(void); +void menudrive(char*); +void pushlast(void); +void poplast(void); +void settings(void); +void singleton(char*); +int subdir(void); + +char next[40]="",cmd[80],last[40]="."; +int val, ok=0; + +#include <string.h> +#define index(s,c) strchr(s,c) + +int main(argc,argv) +int argc; +char *argv[]; +{ char *v=getenv("VIEWER"),*fb=getenv("RETURNTOMENU"); + menuviewer=getenv("MENUVIEWER"); + if(argc>2)fprintf(stderr,"menudriver: wrong number of args\n"),exit(1); +/* +#ifdef VIEWERPAUSESATEND */ + if(!menuviewer)menuviewer="cat"; +/* +#else + if(!menuviewer)menuviewer=viewer; +#endif */ + if(v)viewer=v; + if(fb)fastback=!(*fb=='N'||*fb=='n'); +#ifdef CURSES + setupterm(0,1,&ok); + if(ok!=1)fprintf(stderr,"warning: cannot find terminfo entry\n"); +#endif + menudrive(argc==1?".":argv[1]); } + +int lastval() /* checks if last is a number (and if so leaves value in val) */ +{ if(strcmp(last,".")==0&&subdir()) + /* special case, have just entered subdir */ + { poplast(); + if(sscanf(last,"%d",&val)==1) + { chdir(".."); return(1); } + pushlast(); return(0); } + return(sscanf(last,"%d",&val)==1); +} + +void menudrive(dir) +char *dir; +{ char *np;int c,bad=0; + if(chdir(dir)==-1)singleton(dir); /* apparently not a directory */ + while(stat("contents",&buf)==0) + { if(next[0]=='\0'||bad) + { clrscr(); + /* invalid selection notified here, after clearing screen */ + if(bad) + { if(strcmp(next,".")==0) + printf("no previous selection to substitute for \".\"\n"); + else printf("selection \"%s\" not valid\n",next); + bad=0; } + strcpy(cmd,menuviewer); + strcat(cmd," "); + strcat(cmd,"contents"); + system(cmd); + printf("::please type selection number (or return to exit):"); + /* read remainder of line into next, less leading white space */ + np=next; c=getchar(); + while(c==' '||c=='\t')c=getchar(); + while(c!='\n'&&c!=EOF)*np++=c,c=getchar(); + if(c==EOF)exit(0); + /* remove trailing white space */ + if(next[0]!='!')while(np[-1]==' '||np[-1]=='\t')np--; + *np='\0'; } + if(next[0]=='\0'){ chdir(".."); poplast(); continue; } + if(strcmp(next,".")==0)strcpy(next,last); /* repeat last option */ + if(strcmp(next,"+")==0&&lastval())(void)sprintf(next,"%d",val+1); + if(strcmp(next,"-")==0&&lastval())(void)sprintf(next,"%d",val-1); + if(stat(next,&buf)==0) + { if(strcmp(next,".")==0||strcmp(next,"..")==0||index(next,'/')) + { bad=1; continue; } /* no pathnames - see below */ + if(S_ISDIR(buf.st_mode)) /* directory */ + { char hold[pnlim]; + if(!getcwd(hold,pnlim)) + fprintf(stderr,"panic: cwd too long\n"),exit(1); + if(chdir(next)==-1||stat("contents",&buf)) + bad=1,chdir(hold); + else strcpy(last,next),pushlast(),next[0]='\0'; } else + if(S_ISREG(buf.st_mode)) /* regular file */ + { clrscr(); +#ifndef UWIN + if(buf.st_mode&S_IXUSR) /* executable (by owner) */ +#else + if(strcmp(next,"99")==0) +#endif + { strcpy(cmd,"./"); + strcat(cmd,next); + system(cmd); + if(fastback) + { printf("[Hit return to continue]"); + while(getchar()!='\n'); + } + } else + { strcpy(cmd,viewer); + strcat(cmd," "); + strcat(cmd,next); + system(cmd); } + if(fastback) + { strcpy(last,next); + next[0]='\0'; + } + else + { printf( + "::next selection (or return to go back to menu, or q to quit):" + ); + /* read remainder of line into next, less leading white space */ + strcpy(last,next); + np=next; c=getchar(); + while(c==' '||c=='\t')c=getchar(); + while(c!='\n'&&c!=EOF)*np++=c,c=getchar(); + if(c==EOF)exit(0); + /* remove trailing white space */ + if(next[0]!='!')while(np[-1]==' '||np[-1]=='\t')np--; + *np='\0'; + } + } } else + if(strcmp(next,"???")==0) /* ask to see menudriver settings */ + { settings(); + printf("[Hit return to continue]"); + while(getchar()!='\n'); + next[0]='\0'; + } else + if(strcmp(next,"q")==0||strcmp(next,"/q")==0)exit(0); else + if(next[0]=='!') /* shell escape - handy for editing manual! */ + { static char syscm[80]; + if(next[1]=='\0'||next[1]=='!') + if(syscm[0]) + { if(next[1]=='!')strcat(syscm,next+2); + printf("!%s\n",syscm); } + else + printf("no previous shell command to substitute for \"!\"\n"); + else strcpy(syscm,next+1); + if(syscm[0])callshell(syscm); /* `system' always gets /bin/sh */ + printf("[Hit return to continue]"); + while(getchar()!='\n'); + next[0]='\0'; } + else bad=1; + } +} +/* possibly a bug - can retreat above original dir, if parent contains a + "contents" file - difficult to detect this in a general way, however */ +/* pathnames banned because + (i) upward pathname will not return correctly if a directory (see above) + (ii) direct selection of a grandchild directory leads to + (a) returns via child, instead of directly + (b) meaning of "." is screwed up while in (a) */ +/* could fix all this by - rewrite handling of subdirectory to hold=getwd() + and exit by chdir(hold) instead of chdir("..") - will need to make this + recursive, or else have stack of holdwd's */ + +void singleton(fil) +char *fil; +{ if(stat(fil,&buf)==0 && S_ISREG(buf.st_mode)) /* regular file */ + { clrscr(); +#ifndef UWIN + if(buf.st_mode&S_IXUSR) /* executable (by owner) */ + { strcpy(cmd,"./"); + strcat(cmd,fil); + system(cmd); + fastback=0; } else +#endif + { strcpy(cmd,viewer); + strcat(cmd," "); + strcat(cmd,fil); + system(cmd); } + if(!fastback) + { printf("[Hit return to continue]"); + while(getchar()!='\n'); } + exit(0); + } + else fprintf(stderr,"menudriver: cannot access \"%s\"\n",fil), + exit(1); +} + +void callshell(v) +char v[]; +{ static char *shell=NULL; + sighandler oldsig; int pid; + if(!shell) + { shell=getenv("SHELL"); + if(!shell)shell="/bin/sh"; } + oldsig= signal(SIGINT,SIG_IGN); + if(pid=fork()) + { /* parent */ + if(pid==-1) + perror("UNIX error - cannot create process"); + wait(0); + (void)signal(SIGINT,oldsig); } + else execl(shell,shell,"-c",v,(char *)0); +} + +void settings() +{ printf("current values of menudriver internal variables are\n\n"); + printf(" VIEWER=%s\n",viewer); + printf(" MENUVIEWER=%s\n",menuviewer); + printf(" RETURNTOMENU=%s\n",fastback?"YES":"NO"); + printf("\n\ +These can be modified by setting environment variables of the same names\n\n\ +VIEWER is the program used to display individual sections\n\n\ +MENUVIEWER is the program used to display contents pages\n\n\ +RETURNTOMENU=NO/YES causes a second prompt to be given/not given after\n\ +displaying section (ie before returning to contents page). It should be\n\ +`YES' if VIEWER is a program that pauses for input at end of file, or\n\ +`NO' if VIEWER is a program that quits silently at end of file.\n\n"); +} + +/* +Symptoms of a wrong setting are (i) bottom part of manual section\n\ +disappears from screen before you have had a chance to read it - to cure\n\ +this set RETURNTOMENU=NO; or (ii) having to quit through two layers of\n\ +prompt at bottom of a manual section before getting back to the contents\n\ +page - to cure this set RETURNTOMENU=YES;\n\n"); +*/ + +char lastvec[100],*lastp=lastvec+1; +int giveup=0; + +int subdir() +{ return(lastp>lastvec+1); } + +void pushlast() +{ int n=strlen(last); + if(last[0]=='.') + /* pathological cases */ + if(last[1]=='\0')return; else + if(last[1]=='.'&&last[2]=='\0') + { poplast(); return; } + if(lastp+n>lastvec+100) /* overflow */ + { giveup=1; return; } + /*if(strcmp(lastp,last)==0) + lastp+=n+1,strcpy(last,lastp); else /* here we were */ + /* suppressed 'cos interferes with special case in lastval() */ + strcpy(lastp,last),lastp+=n+1,strcpy(last,"."); +} + +void poplast() +{ strcpy(lastp,last); /* just in case we come back immediately */ + lastp--; + if(giveup||lastp<=lastvec)return; /* underflow */ + while(*--lastp); + strcpy(last,++lastp); +} + +#ifndef CURSES + +/* to clear screen */ +void clrscr() +{ printf("\x1b[2J\x1b[H"); fflush(stdout); +} + +#else +/* alternative method needs curses lib, compile with -DCURSES, or -DUWIN + and -lncurses */ + +#ifdef UWIN +#include <ncurses/curses.h> +#include <ncurses/term.h> +#else +#include <curses.h> +#include <term.h> +#endif + +void clrscr() +{ if(ok!=1)return; + putp(clear_screen); + fflush(stdout); +} +/* end of clrscr method using curses */ +#endif + |