/* 
Program:   execinput.c
Version:   1.0.0
Date:      05-MAR-2002
Author:    David Mathog, Biology Division, Caltech
email:     mathog@caltech.edu
Copyright: 2002 David Mathog and California Institute of Technology (Caltech)

Description:

    Reads input and executes each line via a system() call as long
    as the line is >= 1 character long.  Sometimes handy for putting
    at the end of a long pipe or text file processing stream.  For instance,
    on unix:
    
    find . | grep \/ | extract -cols "mv [1,] [1,-2][cu:-1,]" -dl \/ -mt | execinput
    
    would change all files to upper case.

    Compiles cleanly with:

     % gcc -Wall -pedantic -ansi -o execinput execinput.c
     
    This code will probably compile with any modern C compiler.
    
Changes:

  1.0.0 07-MAR-2002, initial coding.

License terms:
    You may run this program on any platform. You may
    redistribute the source code of this program subject to
    the condition that you do not first modify it in any way.
    You may  distribute binary versions of this program so long
    as they were compiled from unmodified source code.  There
    is no charge for using this software.  You may not charge
    others for the use of this software.


*/

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>            /* for toupper, tolower */
#define EXVERSTRING "1.0.0  07-MAR-2002"
#define MYMAXSTRING 16000
#define NO    0
#define YES   1

/* function prototypes */

void emit_help(void);
int  lcl_strcasecmp(char *s1, char *s2);
void insane(char *string);
void process_command_line_args(int argc,char **argv,int *maxwidth, int *bail);
void setiposnumeric(int *val,int *numarg,int argc,char **argv,char * label);

/* globals */
FILE *lcl_stdin;
FILE *lcl_log;
char *comments;

/* functions */

void insane(char *string){
 (void) fprintf(stderr,"%s\n",string);
 exit(EXIT_FAILURE);
}


void setiposnumeric(int *val,int *numarg,int argc,char **argv,char * label){
      (*numarg)++;
      if( ( *numarg >= argc ) || (argv[*numarg] == NULL)){
        (void) fprintf( stderr, "%s: missing argument\n",label);
        exit(EXIT_FAILURE);
      }
      if(sscanf(argv[*numarg],"%d",val) != 1){
        (void) fprintf(stderr,"Bad integer argument/parameter [%s %s] \n",label,argv[*numarg]);
        exit(EXIT_FAILURE);
      }
      if(*val <= 0){
        (void) fprintf(stderr,"Illegal nonpositive integer argument/parameter [%s %s] \n",label,argv[*numarg]);
        exit(EXIT_FAILURE);
      }
}

int  lcl_strcasecmp(char *s1, char *s2){
int c1;
int c2;
  for(; ;s1++,s2++){
    c1=toupper(*s1);
    c2=toupper(*s2);
    if(c1 < c2)return -1;
    if(c1 > c2)return  1;
    if(c1 == 0)return  0;  /*c2 also is 0 in this case */
  }
}

void emit_help(void){
(void) fprintf(stderr,"execinput command summary:\n\n");
(void) fprintf(stderr,"This program reads one line at a time from stdin or a file\n");
(void) fprintf(stderr,"  and executes it in a subprocess.\n\n");
(void) fprintf(stderr,"  Command line options are.\n");
(void) fprintf(stderr,"   -in   file    input file            (Default = stdin)\n");
(void) fprintf(stderr,"   -logf file    log to file           (Default = no logging)\n");
(void) fprintf(stderr,"   -loge         log to stderr         (Default = no logging)\n");
(void) fprintf(stderr,"   -wl   N       longest command       (Default = %d)\n",MYMAXSTRING);
(void) fprintf(stderr,"   -ef           exit on first failure (Default = continue to end of input)\n");
(void) fprintf(stderr,"   -c    string  lines starting with a character in string are\n");
(void) fprintf(stderr,"                 comments and are not executed. (Default = do all lines)\n");
(void) fprintf(stderr,"   -h            print this help message (also -help --h --help -? --?)\n");
(void) fprintf(stderr,"   -i            emit version, copyright, license and contact information\n\n");
(void) fprintf(stderr,"  Examples (unix):\n\n");
(void) fprintf(stderr,"  %% echo 'mv foo Foo' | execinput\n");
(void) fprintf(stderr,"  %% generate_commands > thecmds ; execinput -in thecmds \n");
exit(EXIT_FAILURE);
}

void  process_command_line_args(int argc,char **argv, 
    int *maxwidth, int *bail){

int  numarg=0;

  
  *maxwidth=MYMAXSTRING;
  *bail=NO;
  lcl_log=NULL;
  lcl_stdin=stdin;
  comments=NULL;
  
  while( ++numarg < argc){
    if( (lcl_strcasecmp(argv[numarg], "-h")==0)     ||
        (lcl_strcasecmp(argv[numarg], "--h")==0)    ||
        (lcl_strcasecmp(argv[numarg], "-?")==0)     ||
        (lcl_strcasecmp(argv[numarg], "--?")==0)    ||
        (lcl_strcasecmp(argv[numarg], "-help")==0)  ||
        (lcl_strcasecmp(argv[numarg], "--help")==0) ){
      emit_help();
    }
    else if(lcl_strcasecmp(argv[numarg], "-i")==0){
      (void)fprintf(stderr,"Version:   %s\n",EXVERSTRING);
      (void)fprintf(stderr,"bugs to:   mathog@caltech.edu\n");
      (void)fprintf(stderr,"Copyright: 2002 David Mathog and California Institute of Technology\n");
      (void)fprintf(stderr,"License terms:\n");
      (void)fprintf(stderr,"    You may run this program on any platform. You may\n");
      (void)fprintf(stderr,"    redistribute the source code of this program subject to\n");
      (void)fprintf(stderr,"    the condition that you do not first modify it in any way.\n");
      (void)fprintf(stderr,"    You may  distribute binary versions of this program so long\n");
      (void)fprintf(stderr,"    as they were compiled from unmodified source code.  There\n");
      (void)fprintf(stderr,"    is no charge for using this software.  You may not charge\n");
      (void)fprintf(stderr,"    others for the use of this software.\n");
      exit(EXIT_SUCCESS);
    }
    else if(lcl_strcasecmp(argv[numarg], "-c")==0){
      comments=argv[++numarg];
      continue;
    }
    else if(lcl_strcasecmp(argv[numarg], "-wl")==0){
      setiposnumeric(maxwidth,&numarg,argc,argv,"-wl");
      continue;
    }
    else if(lcl_strcasecmp(argv[numarg], "-in")==0){
      lcl_stdin=fopen(argv[++numarg],"r");
      if(lcl_stdin==NULL)insane("execinput: fatal error: could not open input file");
      continue;
    }
    else if(lcl_strcasecmp(argv[numarg], "-logf")==0){
      lcl_log=fopen(argv[++numarg],"w");
      if(lcl_log==NULL)insane("execinput: fatal error: could not open log file");
      continue;
    }
    else if(lcl_strcasecmp(argv[numarg], "-loge")==0){
      lcl_log=stderr;
      continue;
    }
    else if(lcl_strcasecmp(argv[numarg], "-ef")==0){
      *bail=YES;
      continue;
    }
    else {
       (void) fprintf(stderr,"execinput: fatal error: on command line [%s] is not recognized.  Use the -h flag to list options.\n",argv[numarg]);
       exit(EXIT_FAILURE);
    }
  }

  /* sanity checking */
   
}


int main(int argc, char *argv[]){
/* command line values */

int maxwidth,bail;

/* other values */
int outstat;
char *buffer;   /* buffer to hold lines */
char *newline;  /* used to point to newline in buffer */

  process_command_line_args(argc,argv,&maxwidth,&bail);
    
  buffer=malloc(sizeof(char)*(maxwidth+1));
  if(buffer == NULL){
      insane("execinput: fatal error: icould not allocate character buffer\n");
  }
  while( fgets(buffer,maxwidth,lcl_stdin) != NULL){
    newline=strstr(buffer,"\n");
    if(newline == NULL){   /* string truncated, this is fatal in this program */
      (void) fprintf(stderr,"execinput: fatal error: input line was longer than %d\n",maxwidth);
      exit(EXIT_FAILURE);
    }
    *newline='\0';                        /* replace the \n with a terminator */
    if(comments==NULL || strchr(comments,buffer[0]) == NULL){
      outstat=system(buffer);
      if(outstat==EXIT_SUCCESS){
        if(lcl_log != NULL)(void) fprintf(lcl_log,"success:%8.8x: %s\n",outstat,buffer);
      }
      else {
        if(lcl_log != NULL)(void) fprintf(lcl_log,"failed: %8.8x: %s\n",outstat,buffer);
        if(bail==YES)exit(EXIT_FAILURE);
      }
    }
    else {
        if(lcl_log != NULL)(void) fprintf(lcl_log,"comment: 00000000: %s\n",buffer);
    }
  }
  exit(EXIT_SUCCESS);
}