vcs.maemo.org Git - monky/blob - src/tailhead.c

   1 /* -*- mode: c; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: t -*-
   2  * vim: ts=4 sw=4 noet ai cindent syntax=c
   3  *
   4  * Conky, a system monitor, based on torsmo
   5  *
   6  * Any original torsmo code is licensed under the BSD license
   7  *
   8  * All code written since the fork of torsmo is licensed under the GPL
   9  *
  10  * Please see COPYING for details
  11  *
  12  * Copyright (c) 2004, Hannu Saransaari and Lauri Hakkarainen
  13  * Copyright (c) 2005-2010 Brenden Matthews, Philip Kovacs, et. al.
  14  *      (see AUTHORS)
  15  * All rights reserved.
  16  *
  17  * This program is free software: you can redistribute it and/or modify
  18  * it under the terms of the GNU General Public License as published by
  19  * the Free Software Foundation, either version 3 of the License, or
  20  * (at your option) any later version.
  21  *
  22  * This program is distributed in the hope that it will be useful,
  23  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  24  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  25  * GNU General Public License for more details.
  26  * You should have received a copy of the GNU General Public License
  27  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  28  *
  29  */
  30
  31 #define _GNU_SOURCE
  32 #include "common.h"
  33 #include "text_object.h"
  34 #include "logging.h"
  35 #include <sys/stat.h>
  36 #include <ctype.h>
  37 #include <fcntl.h>
  38 #include <string.h>
  39 #include <unistd.h>
  40
  41 #define MAX_HEADTAIL_LINES 30
  42 #define DEFAULT_MAX_HEADTAIL_USES 2
  43
  44 struct headtail {
  45         int wantedlines;
  46         char *logfile;
  47         char *buffer;
  48         int current_use;
  49         int max_uses;
  50         int reported;
  51 };
  52
  53 static void tailstring(char *string, int endofstring, int wantedlines) {
  54         int i, linescounted = 0;
  55
  56         string[endofstring] = 0;
  57         if(endofstring > 0) {
  58                 if(string[endofstring-1] == '\n') {     //work with or without \n at end of file
  59                         string[endofstring-1] = 0;
  60                 }
  61                 for(i = endofstring - 1; i >= 0 && linescounted < wantedlines; i--) {
  62                         if(string[i] == '\n') {
  63                                 linescounted++;
  64                         }
  65                 }
  66                 if(i > 0) {
  67                         strfold(string, i+2);
  68                 }
  69         }
  70 }
  71
  72 void free_tailhead(struct text_object *obj)
  73 {
  74         struct headtail *ht = obj->data.opaque;
  75         if (!ht)
  76                 return;
  77         if (ht->logfile)
  78                 free(ht->logfile);
  79         if (ht->buffer)
  80                 free(ht->buffer);
  81         free(obj->data.opaque);
  82         obj->data.opaque = NULL;
  83 }
  84
  85 void init_tailhead(const char* type, const char* arg, struct text_object *obj, void* free_at_crash) {
  86         unsigned int args;
  87         struct headtail *ht;
  88
  89         ht = malloc(sizeof(struct headtail));
  90         memset(ht, 0, sizeof(struct headtail));
  91
  92         ht->logfile = malloc(DEFAULT_TEXT_BUFFER_SIZE);
  93         memset(ht->logfile, 0, DEFAULT_TEXT_BUFFER_SIZE);
  94
  95         ht->max_uses = DEFAULT_MAX_HEADTAIL_USES;
  96
  97         args = sscanf(arg, "%s %d %d", ht->logfile, &ht->wantedlines, &ht->max_uses);
  98         if (args < 2 || args > 3) {
  99                 free_tailhead(obj);
 100                 CRIT_ERR(obj, free_at_crash, "%s needs a file as 1st and a number of lines as 2nd argument", type);
 101         }
 102         if (ht->max_uses < 1) {
 103                 free_tailhead(obj);
 104                 CRIT_ERR(obj, free_at_crash, "invalid arg for %s, next_check must be larger than 0", type);
 105         }
 106         if (ht->wantedlines > 0 && ht->wantedlines <= MAX_HEADTAIL_LINES) {
 107                 to_real_path(ht->logfile, ht->logfile);
 108                 ht->buffer = NULL;
 109                 ht->current_use = 0;
 110         } else {
 111                 free_tailhead(obj);
 112                 CRIT_ERR(obj, free_at_crash, "invalid arg for %s, number of lines must be between 1 and %d", type, MAX_HEADTAIL_LINES);
 113         }
 114         obj->data.opaque = ht;
 115 }
 116
 117 void print_tailhead(const char* type, struct text_object *obj, char *p, int p_max_size) {
 118         int fd, i, endofstring = 0, linescounted = 0;
 119         FILE *fp;
 120         struct stat st;
 121         struct headtail *ht = obj->data.opaque;
 122
 123         if (!ht)
 124                 return;
 125
 126         //empty the buffer and reset the counter if we used it the max number of times
 127         if(ht->buffer && ht->current_use >= ht->max_uses - 1) {
 128                 free(ht->buffer);
 129                 ht->buffer = NULL;
 130                 ht->current_use = 0;
 131         }
 132         //use the buffer if possible
 133         if(ht->buffer) {
 134                 strcpy(p, ht->buffer);
 135                 ht->current_use++;
 136         }else{  //otherwise find the needed data
 137                 if(stat(ht->logfile, &st) == 0) {
 138                         if (S_ISFIFO(st.st_mode)) {
 139                                 fd = open_fifo(ht->logfile, &ht->reported);
 140                                 if(fd != -1) {
 141                                         if(strcmp(type, "head") == 0) {
 142                                                 for(i = 0; linescounted < ht->wantedlines; i++) {
 143                                                         read(fd, p + i, 1);
 144                                                         if(p[i] == '\n') {
 145                                                                 linescounted++;
 146                                                         }
 147                                                 }
 148                                                 p[i] = 0;
 149                                         } else if(strcmp(type, "tail") == 0) {
 150                                                 i = read(fd, p, p_max_size - 1);
 151                                                 tailstring(p, i, ht->wantedlines);
 152                                         } else {
 153                                                 CRIT_ERR(NULL, NULL, "If you are seeing this then there is a bug in the code, report it !");
 154                                         }
 155                                 }
 156                                 close(fd);
 157                         } else {
 158                                 fp = open_file(ht->logfile, &ht->reported);
 159                                 if(fp != NULL) {
 160                                         if(strcmp(type, "head") == 0) {
 161                                                 for(i = 0; i < ht->wantedlines; i++) {
 162                                                         fgets(p + endofstring, p_max_size - endofstring, fp);
 163                                                         endofstring = strlen(p);
 164                                                 }
 165                                         } else if(strcmp(type, "tail") == 0) {
 166                                                 fseek(fp, - p_max_size, SEEK_END);
 167                                                 i = fread(p, 1, p_max_size - 1, fp);
 168                                                 tailstring(p, i, ht->wantedlines);
 169                                         } else {
 170                                                 CRIT_ERR(NULL, NULL, "If you are seeing this then there is a bug in the code, report it !");
 171                                         }
 172                                         fclose(fp);
 173                                 }
 174                         }
 175                         ht->buffer = strdup(p);
 176                 } else {
 177                         CRIT_ERR(NULL, NULL, "$%s can't find information about %s", type, ht->logfile);
 178                 }
 179         }
 180         return;
 181 }
 182
 183 /* FIXME: use something more general (see also tail.c, head.c */
 184 #define BUFSZ 0x1000
 185
 186 void print_lines(struct text_object *obj, char *p, int p_max_size)
 187 {
 188         static int rep = 0;
 189         FILE *fp = open_file(obj->data.s, &rep);
 190         char buf[BUFSZ];
 191         int j, lines;
 192
 193         if (!fp) {
 194                 snprintf(p, p_max_size, "File Unreadable");
 195                 return;
 196         }
 197
 198         lines = 0;
 199         while(fgets(buf, BUFSZ, fp) != NULL){
 200                 for(j = 0; buf[j] != 0; j++) {
 201                         if(buf[j] == '\n') {
 202                                 lines++;
 203                         }
 204                 }
 205         }
 206         snprintf(p, p_max_size, "%d", lines);
 207         fclose(fp);
 208 }
 209
 210 void print_words(struct text_object *obj, char *p, int p_max_size)
 211 {
 212         static int rep = 0;
 213         FILE *fp = open_file(obj->data.s, &rep);
 214         char buf[BUFSZ];
 215         int j, words;
 216         char inword = 0;
 217
 218         if(!fp) {
 219                 snprintf(p, p_max_size, "File Unreadable");
 220                 return;
 221         }
 222
 223         words = 0;
 224         while(fgets(buf, BUFSZ, fp) != NULL){
 225                 for(j = 0; buf[j] != 0; j++) {
 226                         if(!isspace(buf[j])) {
 227                                 if(!inword) {
 228                                         words++;
 229                                         inword = 1;
 230                                 }
 231                         } else {
 232                                 inword = 0;
 233                         }
 234                 }
 235         }
 236         snprintf(p, p_max_size, "%d", words);
 237         fclose(fp);
 238 }