sortformat.c

linux下获取一些环境信息的代码

/*
 * Copyright 1998-2004 by Albert Cahalan; all rights resered.         
 * This file may be used subject to the terms and conditions of the
 * GNU Library General Public License Version 2, or any later version  
 * at your option, as published by the Free Software Foundation.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Library General Public License for more details.
 */                                 

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

/* username lookups */
#include <sys/types.h>
#include <pwd.h>
#include <grp.h>

#include "../proc/readproc.h"
#include "../proc/sysinfo.h"
#include "common.h"

static sf_node *sf_list = NULL;         /* deferred sorting and formatting */
static int broken;                      /* use gross Unix98 parsing? */
static int have_gnu_sort = 0;           /* if true, "O" must be format */
static int already_parsed_sort = 0;     /* redundantly set in & out of fn */
static int already_parsed_format = 0;


/****************  Parse single format specifier *******************/
static format_node *do_one_spec(const char *spec, const char *override){
  const format_struct *fs;
  const macro_struct *ms;

  fs = search_format_array(spec);
  if(fs){
    int w1, w2;
    format_node *thisnode;
    thisnode = malloc(sizeof(format_node));
    if(fs->flags & CF_PIDMAX){
      w1 = (int)get_pid_digits();
      w2 = strlen(fs->head);
      if(w2>w1) w1=w2; // FIXME w/ separate header/body column sizing
    }else{
      w1 = fs->width;
    }
    if(override){
      w2 = strlen(override);
      thisnode->width = (w1>w2)?w1:w2;
      thisnode->name = malloc(strlen(override)+1);
      strcpy(thisnode->name, override);
    }else{
      thisnode->width = w1;
      thisnode->name = malloc(strlen(fs->head)+1);
      strcpy(thisnode->name, fs->head);
    }
    thisnode->pr = fs->pr;
    thisnode->need = fs->need;
    thisnode->vendor = fs->vendor;
    thisnode->flags = fs->flags;
    thisnode->next = NULL;
    return thisnode;
  }

  /* That failed, so try it as a macro. */
  ms = search_macro_array(spec);
  if(ms){
    format_node *list = NULL;
    format_node *newnode;
    const char *walk;
    int dist;
    char buf[16]; /* trust strings will be short (from above, not user) */
    walk = ms->head;
    while(*walk){
      dist = strcspn(walk, ", ");
      strncpy(buf,walk,dist);
      buf[dist] = '\0';
      newnode = do_one_spec(buf,override); /* call self, assume success */
      newnode->next = list;
      list = newnode;
      walk += dist;
      if(*walk) walk++;
    }
    return list;
  }
  return NULL;   /* bad, spec not found */
}


/************ must wrap user format in default *************/
static void O_wrap(sf_node *sfn, int otype){
  format_node *fnode;
  format_node *endp;
  const char *trailer;

  trailer = (otype=='b') ? "END_BSD" : "END_SYS5" ;

  fnode =  do_one_spec("pid",NULL);
  if(!fnode)fprintf(stderr,"Seriously crashing. Goodbye cruel world.\n");
  endp = sfn->f_cooked; while(endp->next) endp = endp->next;  /* find end */
  endp->next = fnode;
  
  fnode =  do_one_spec(trailer,NULL);
  if(!fnode)fprintf(stderr,"Seriously crashing. Goodbye cruel world.\n");
  endp = fnode; while(endp->next) endp = endp->next;  /* find end */
  endp->next = sfn->f_cooked;
  sfn->f_cooked = fnode;
}

/******************************************************************
 * Used to parse option AIX field descriptors.
 * Put each completed format_node onto the list starting at ->f_cooked
 */
static const char *aix_format_parse(sf_node *sfn){
  char *buf;                   /* temp copy of arg to hack on */
  char *walk;
  int items;

  /*** sanity check and count items ***/
  items = 0;
  walk = sfn->sf;
  /* state machine */ {
  int c;
  initial:
    c = *walk++;
    if(c=='%')    goto get_desc;
    if(!c)        goto looks_ok;
  /* get_text: */
    items++;
  get_more_text:
    c = *walk++;
    if(c=='%')    goto get_desc;
    if(c)         goto get_more_text;
    goto looks_ok;
  get_desc:
    items++;
    c = *walk++;
    if(c)         goto initial;
    return "Improper AIX field descriptor.";
  looks_ok:
    ;
  }

  /*** sanity check passed ***/
  buf = malloc(strlen(sfn->sf)+1);
  strcpy(buf, sfn->sf);
  walk = sfn->sf;
  
  while(items--){
    format_node *fnode;  /* newly allocated */
    format_node *endp;   /* for list manipulation */

    if(*walk == '%'){
      const aix_struct *aix;
      walk++;
      if(*walk == '%') goto double_percent;
      aix = search_aix_array(*walk);
      walk++;
      if(!aix){
        free(buf);
        return "Unknown AIX field descriptor.";
      }
      fnode =  do_one_spec(aix->spec, aix->head);
      if(!fnode){
        free(buf);
        return "AIX field descriptor processing bug.";
      }
    } else {
      int len;
      len = strcspn(walk, "%");
      memcpy(buf,walk,len);
      if(0){
double_percent:
        len = 1;
        buf[0] = '%';
      }
      buf[len] = '\0';
      walk += len;
      fnode = malloc(sizeof(format_node));
      fnode->width = len;
      fnode->name = malloc(len+1);
      strcpy(fnode->name, buf);
      fnode->pr = NULL;     /* checked for */
      fnode->need = 0;
      fnode->vendor = AIX;
      fnode->flags = CF_PRINT_EVERY_TIME;
      fnode->next = NULL;
    }
    
    endp = fnode; while(endp->next) endp = endp->next;  /* find end */
    endp->next = sfn->f_cooked;
    sfn->f_cooked = fnode;
  }
  free(buf);
  already_parsed_format = 1;
  return NULL;
}

/***************************************************************
 * Used to parse option O lists. Option O is shared between
 * sorting and formatting. Users may expect one or the other.
 * The "broken" flag enables a really bad Unix98 misfeature.
 * Put each completed format_node onto the list starting at ->f_cooked
 */
static const char *format_parse(sf_node *sfn){
  char *buf;                   /* temp copy of arg to hack on */
  char *sep_loc;               /* separator location: " \t,\n" */
  char *walk;
  const char *err;       /* error code that could or did happen */
  format_node *fnode;
  int items;
  int need_item;
  static char errbuf[80]; /* for variable-text error message */

  /*** prepare to operate ***/
  buf = malloc(strlen(sfn->sf)+1);
  strcpy(buf, sfn->sf);
  
  /*** sanity check and count items ***/
  need_item = 1; /* true */
  items = 0;
  walk = buf;
  do{
    switch(*walk){
    case ' ': case ',': case '\t': case '\n': case '\0':
    /* Linux extension: allow \t and \n as delimiters */
      if(need_item){
        free(buf);
        goto improper;
      }
      need_item=1;
      break;
    case '=':
      if(broken) goto out;
      /* fall through */
    default:
      if(need_item) items++;
      need_item=0;
    }
  } while (*++walk);
out:
  if(!items){
    free(buf);
    goto empty;
  }
#ifdef STRICT_LIST
  if(need_item){    /* can't have trailing deliminator */
    free(buf);
    goto improper;
  }
#else
  if(need_item){    /* allow 1 trailing deliminator */
    *--walk='\0';  /* remove the trailing deliminator */
  }
#endif
  /*** actually parse the list ***/
  walk = buf;
  while(items--){
    format_node *endp;
    char *equal_loc;
    char *colon_loc;
    sep_loc = strpbrk(walk," ,\t\n");
    /* if items left, then sep_loc is not in header override */
    if(items && sep_loc) *sep_loc = '\0';
    equal_loc = strpbrk(walk,"=");
    if(equal_loc){   /* if header override */
      *equal_loc = '\0';
      equal_loc++;
    }
    colon_loc = strpbrk(walk,":");
    if(colon_loc){   /* if width override */
      *colon_loc = '\0';
      colon_loc++;
      if(strspn(colon_loc,"0123456789") != strlen(colon_loc) || *colon_loc=='0' || !*colon_loc){
        free(buf);
        goto badwidth;
      }
    }
    fnode =  do_one_spec(walk,equal_loc);
    if(!fnode){
      if(!*errbuf){  /* if didn't already create an error string */
        snprintf(
          errbuf,
          sizeof(errbuf),
          "Unknown user-defined format specifier \"%s\".",
          walk
        );
      }
      free(buf);
      goto unknown;
    }
    if(colon_loc){
      if(fnode->next){
        free(buf);
        goto notmacro;
      }
      // FIXME: enforce signal width to 8, 9, or 16 (grep: SIGNAL wide_signals)
      fnode->width = atoi(colon_loc); // already verified to be a number
    }
    endp = fnode; while(endp->next) endp = endp->next;  /* find end */
    endp->next = sfn->f_cooked;
    sfn->f_cooked = fnode;
    walk = sep_loc + 1; /* point to next item, if any */
  }
  free(buf);
  already_parsed_format = 1;
  return NULL;

  /* errors may cause a retry looking for AIX format codes */
  if(0) unknown:  err=errbuf;
  if(0) empty:    err="Empty format list.";
  if(0) improper: err="Improper format list.";
  if(0) badwidth: err="Column widths must be unsigned decimal numbers.";
  if(0) notmacro: err="Can't set width for a macro (multi-column) format specifier.";
  if(strchr(sfn->sf,'%')) err = aix_format_parse(sfn);
  return err;
}

/****************  Parse single sort specifier *******************/
static sort_node *do_one_sort_spec(const char *spec){
  const format_struct *fs;
  int reverse = 0;
  if(*spec == '-'){
    reverse = 1;
    spec++;
  }
  fs = search_format_array(spec);
  if(fs){
    sort_node *thisnode;
    thisnode = malloc(sizeof(sort_node));
    thisnode->sr = fs->sr;
    thisnode->need = fs->need;
    thisnode->reverse = reverse;
    thisnode->next = NULL;
    return thisnode;
  }
  return NULL;   /* bad, spec not found */
}


/**************************************************************
 * Used to parse long sorting options.
 * Put each completed sort_node onto the list starting at ->s_cooked
 */
static const char *long_sort_parse(sf_node *sfn){
  char *buf;                   /* temp copy of arg to hack on */
  char *sep_loc;               /* separator location: " \t,\n" */
  char *walk;
  sort_node *snode;
  int items;
  int need_item;

  /*** prepare to operate ***/
  buf = malloc(strlen(sfn->sf)+1);
  strcpy(buf, sfn->sf);
  
  /*** sanity check and count items ***/
  need_item = 1; /* true */
  items = 0;
  walk = buf;
  do{
    switch(*walk){
    case ' ': case ',': case '\t': case '\n': case '\0':
      if(need_item){
        free(buf);
        return "Improper sort list";
      }
      need_item=1;
      break;
    default:
      if(need_item) items++;
      need_item=0;
    }
  } while (*++walk);
  if(!items){
    free(buf);
    return "Empty sort list.";
  }
#ifdef STRICT_LIST
  if(need_item){    /* can't have trailing deliminator */
    free(buf);
    return "Improper sort list.";
  }
#else
  if(need_item){    /* allow 1 trailing deliminator */
    *--walk='\0';  /* remove the trailing deliminator */
  }
#endif
  /*** actually parse the list ***/
  walk = buf;
  while(items--){
    sort_node *endp;
    sep_loc = strpbrk(walk," ,\t\n");
    if(sep_loc) *sep_loc = '\0';
    snode = do_one_sort_spec(walk);
    if(!snode){
      free(buf);
      return "Unknown sort specifier.";
    }
    endp = snode; while(endp->next) endp = endp->next;  /* find end */
    endp->next = sfn->s_cooked;
    sfn->s_cooked = snode;
    walk = sep_loc + 1; /* point to next item, if any */
  }
  free(buf);
  already_parsed_sort = 1;
  return NULL;
}






/************ pre-parse short sorting option *************/
/* Errors _must_ be detected so that the "O" option can try to
 * reparse as formatting codes.
 */
static const char *verify_short_sort(const char *arg){
  const char all[] = "CGJKMNPRSTUcfgjkmnoprstuvy+-";
  char checkoff[256];
  int i;
  const char *walk;
  int tmp;
  if(strspn(arg,all) != strlen(arg)) return "Bad sorting code.";
  for(i=256; i--;) checkoff[i] = 0;
  walk = arg;
  for(;;){
    tmp = *walk;
    switch(tmp){
    case '\0':
      return NULL;   /* looks good */
    case '+':
    case '-':
      tmp = *(walk+1);
      if(!tmp || tmp=='+' || tmp=='-') return "Bad sorting code.";
      break;
    case 'P':
      if(forest_type) return "PPID sort and forest output conflict.";
      /* fall through */
    default:
      if(checkoff[tmp]) return "Bad sorting code.";   /* repeated */
      /* ought to check against already accepted sort options */
      checkoff[tmp] = 1;
      break;
    }
    walk++;
  }
}



/************ parse short sorting option *************/
static const char *short_sort_parse(sf_node *sfn){
  int direction = 0;
  const char *walk;
  int tmp;
  sort_node *snode;
  sort_node *endp;
  const struct shortsort_struct *ss;
  walk = sfn->sf;
  for(;;){
    tmp = *walk;
    switch(tmp){
    case '\0':
      already_parsed_sort = 1;
      return NULL;
    case '+':
      direction = 0;
      break;
    case '-':
      direction = 1;
      break;
    default:
      ss = search_shortsort_array(tmp);