1 /*****************************************************************************
2 * RRDtool 1.1.x Copyright Tobias Oetiker, 1997 - 2002
3 *****************************************************************************
4 * rrd_open.c Open an RRD File
5 *****************************************************************************
6 * $Id$
7 * $Log$
8 * Revision 1.8 2003/04/11 19:43:44 oetiker
9 * New special value COUNT which allows calculations based on the position of a
10 * value within a data set. Bug fix in rrd_rpncalc.c. PREV returned erroneus
11 * value for the second value. Bug fix in rrd_restore.c. Bug causing seek error
12 * when accesing an RRD restored from an xml that holds an RRD version <3.
13 * -- Ruben Justo <ruben@ainek.com>
14 *
15 * Revision 1.7 2003/03/31 21:22:12 oetiker
16 * enables RRDtool updates with microsecond or in case of windows millisecond
17 * precision. This is needed to reduce time measurement error when archive step
18 * is small. (<30s) -- Sasha Mikheev <sasha@avalon-net.co.il>
19 *
20 * Revision 1.6 2003/02/13 07:05:27 oetiker
21 * Find attached the patch I promised to send to you. Please note that there
22 * are three new source files (src/rrd_is_thread_safe.h, src/rrd_thread_safe.c
23 * and src/rrd_not_thread_safe.c) and the introduction of librrd_th. This
24 * library is identical to librrd, but it contains support code for per-thread
25 * global variables currently used for error information only. This is similar
26 * to how errno per-thread variables are implemented. librrd_th must be linked
27 * alongside of libpthred
28 *
29 * There is also a new file "THREADS", holding some documentation.
30 *
31 * -- Peter Stamfest <peter@stamfest.at>
32 *
33 * Revision 1.5 2002/06/20 00:21:03 jake
34 * More Win32 build changes; thanks to Kerry Calvert.
35 *
36 * Revision 1.4 2002/02/01 20:34:49 oetiker
37 * fixed version number and date/time
38 *
39 * Revision 1.3 2001/03/04 13:01:55 oetiker
40 * Aberrant Behavior Detection support. A brief overview added to rrdtool.pod.
41 * Major updates to rrd_update.c, rrd_create.c. Minor update to other core files.
42 * This is backwards compatible! But new files using the Aberrant stuff are not readable
43 * by old rrdtool versions. See http://cricket.sourceforge.net/aberrant/rrd_hw.htm
44 * -- Jake Brutlag <jakeb@corp.webtv.net>
45 *
46 * Revision 1.2 2001/03/04 10:29:20 oetiker
47 * fixed filedescriptor leak
48 * -- Mike Franusich <mike@franusich.com>
49 *
50 * Revision 1.1.1.1 2001/02/25 22:25:05 oetiker
51 * checkin
52 *
53 *****************************************************************************/
55 #include "rrd_tool.h"
56 #define MEMBLK 8192
58 /* open a database file, return its header and a open filehandle */
59 /* positioned to the first cdp in the first rra */
61 int
62 rrd_open(char *file_name, FILE **in_file, rrd_t *rrd, int rdwr)
63 {
66 char *mode = NULL;
67 int version;
69 rrd_init(rrd);
70 if (rdwr == RRD_READONLY) {
71 #ifndef WIN32
72 mode = "r";
73 #else
74 mode = "rb";
75 #endif
76 } else {
77 #ifndef WIN32
78 mode = "r+";
79 #else
80 mode = "rb+";
81 #endif
82 }
84 if (((*in_file) = fopen(file_name,mode)) == NULL ){
85 rrd_set_error("opening '%s': %s",file_name, rrd_strerror(errno));
86 return (-1);
87 }
88 /*
89 if (rdwr == RRD_READWRITE)
90 {
91 if (setvbuf((*in_file),NULL,_IONBF,2)) {
92 rrd_set_error("failed to disable the stream buffer\n");
93 return (-1);
94 }
95 }
96 */
98 #define MYFREAD(MYVAR,MYVART,MYCNT) \
99 if ((MYVAR = malloc(sizeof(MYVART) * MYCNT)) == NULL) {\
100 rrd_set_error("" #MYVAR " malloc"); \
101 fclose(*in_file); \
102 return (-1); } \
103 fread(MYVAR,sizeof(MYVART),MYCNT, *in_file);
106 MYFREAD(rrd->stat_head, stat_head_t, 1)
107 version = atoi(rrd->stat_head->version);
109 /* lets do some test if we are on track ... */
110 if (strncmp(rrd->stat_head->cookie,RRD_COOKIE,4) != 0){
111 rrd_set_error("'%s' is not an RRD file",file_name);
112 free(rrd->stat_head);
113 fclose(*in_file);
114 return(-1);}
116 if (version > atoi(RRD_VERSION)){
117 rrd_set_error("can't handle RRD file version %s",
118 rrd->stat_head->version);
119 free(rrd->stat_head);
120 fclose(*in_file);
121 return(-1);}
123 if (rrd->stat_head->float_cookie != FLOAT_COOKIE){
124 rrd_set_error("This RRD was created on other architecture");
125 free(rrd->stat_head);
126 fclose(*in_file);
127 return(-1);}
129 MYFREAD(rrd->ds_def, ds_def_t, rrd->stat_head->ds_cnt)
130 MYFREAD(rrd->rra_def, rra_def_t, rrd->stat_head->rra_cnt)
131 /* handle different format for the live_head */
132 if(version < 3) {
133 rrd->live_head = (live_head_t *)malloc(sizeof(live_head_t));
134 if(rrd->live_head == NULL) {
135 rrd_set_error("live_head_t malloc");
136 fclose(*in_file);
137 return (-1);
138 }
139 fread(&rrd->live_head->last_up, sizeof(long), 1, *in_file);
140 rrd->live_head->last_up_usec = 0;
141 }
142 else {
143 MYFREAD(rrd->live_head, live_head_t, 1)
144 }
145 MYFREAD(rrd->pdp_prep, pdp_prep_t, rrd->stat_head->ds_cnt)
146 MYFREAD(rrd->cdp_prep, cdp_prep_t, (rrd->stat_head->rra_cnt
147 * rrd->stat_head->ds_cnt))
148 MYFREAD(rrd->rra_ptr, rra_ptr_t, rrd->stat_head->rra_cnt)
149 #undef MYFREAD
151 return(0);
152 }
154 void rrd_init(rrd_t *rrd)
155 {
156 rrd->stat_head = NULL;
157 rrd->ds_def = NULL;
158 rrd->rra_def = NULL;
159 rrd->live_head = NULL;
160 rrd->rra_ptr = NULL;
161 rrd->pdp_prep = NULL;
162 rrd->cdp_prep = NULL;
163 rrd->rrd_value = NULL;
164 }
166 void rrd_free(rrd_t *rrd)
167 {
168 if (rrd->stat_head) free(rrd->stat_head);
169 if (rrd->ds_def) free(rrd->ds_def);
170 if (rrd->rra_def) free(rrd->rra_def);
171 if (rrd->live_head) free(rrd->live_head);
172 if (rrd->rra_ptr) free(rrd->rra_ptr);
173 if (rrd->pdp_prep) free(rrd->pdp_prep);
174 if (rrd->cdp_prep) free(rrd->cdp_prep);
175 if (rrd->rrd_value) free(rrd->rrd_value);
176 }
178 /* routine used by external libraries to free memory allocated by
179 * rrd library */
180 void rrd_freemem(void *mem)
181 {
183 if (mem) free(mem);
184 }
186 int readfile(char *file_name, char **buffer, int skipfirst){
187 long writecnt=0,totalcnt = MEMBLK;
188 FILE *input=NULL;
189 char c ;
190 if ((strcmp("-",file_name) == 0)) { input = stdin; }
191 else {
192 if ((input = fopen(file_name,"rb")) == NULL ){
193 rrd_set_error("opening '%s': %s",file_name,rrd_strerror(errno));
194 return (-1);
195 }
196 }
197 if (skipfirst){
198 do { c = getc(input); } while (c != '\n' && ! feof(input));
199 }
200 if (((*buffer) = (char *) malloc((MEMBLK+4)*sizeof(char))) == NULL) {
201 perror("Allocate Buffer:");
202 exit(1);
203 };
204 do{
205 writecnt += fread((*buffer)+writecnt, 1, MEMBLK * sizeof(char) ,input);
206 if (writecnt >= totalcnt){
207 totalcnt += MEMBLK;
208 if (((*buffer)=rrd_realloc((*buffer), (totalcnt+4) * sizeof(char)))==NULL){
209 perror("Realloc Buffer:");
210 exit(1);
211 };
212 }
213 } while (! feof(input));
214 (*buffer)[writecnt] = '\0';
215 if (strcmp("-",file_name) != 0) {fclose(input);};
216 return writecnt;
217 }