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testlo64.c
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1 /*-------------------------------------------------------------------------
2  *
3  * testlo64.c
4  * test using large objects with libpq using 64-bit APIs
5  *
6  * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  *
10  * IDENTIFICATION
11  * src/test/examples/testlo64.c
12  *
13  *-------------------------------------------------------------------------
14  */
15 #include <stdio.h>
16 #include <stdlib.h>
17 
18 #include <sys/types.h>
19 #include <sys/stat.h>
20 #include <fcntl.h>
21 #include <unistd.h>
22 
23 #include "libpq-fe.h"
24 #include "libpq/libpq-fs.h"
25 
26 #define BUFSIZE 1024
27 
28 /*
29  * importFile -
30  * import file "in_filename" into database as large object "lobjOid"
31  *
32  */
33 static Oid
35 {
36  Oid lobjId;
37  int lobj_fd;
38  char buf[BUFSIZE];
39  int nbytes,
40  tmp;
41  int fd;
42 
43  /*
44  * open the file to be read in
45  */
46  fd = open(filename, O_RDONLY, 0666);
47  if (fd < 0)
48  { /* error */
49  fprintf(stderr, "cannot open unix file\"%s\"\n", filename);
50  }
51 
52  /*
53  * create the large object
54  */
55  lobjId = lo_creat(conn, INV_READ | INV_WRITE);
56  if (lobjId == 0)
57  fprintf(stderr, "cannot create large object");
58 
59  lobj_fd = lo_open(conn, lobjId, INV_WRITE);
60 
61  /*
62  * read in from the Unix file and write to the inversion file
63  */
64  while ((nbytes = read(fd, buf, BUFSIZE)) > 0)
65  {
66  tmp = lo_write(conn, lobj_fd, buf, nbytes);
67  if (tmp < nbytes)
68  fprintf(stderr, "error while reading \"%s\"", filename);
69  }
70 
71  close(fd);
72  lo_close(conn, lobj_fd);
73 
74  return lobjId;
75 }
76 
77 static void
79 {
80  int lobj_fd;
81  char *buf;
82  int nbytes;
83  int nread;
84 
85  lobj_fd = lo_open(conn, lobjId, INV_READ);
86  if (lobj_fd < 0)
87  fprintf(stderr, "cannot open large object %u", lobjId);
88 
89  if (lo_lseek64(conn, lobj_fd, start, SEEK_SET) < 0)
90  fprintf(stderr, "error in lo_lseek64: %s", PQerrorMessage(conn));
91 
92  if (lo_tell64(conn, lobj_fd) != start)
93  fprintf(stderr, "error in lo_tell64: %s", PQerrorMessage(conn));
94 
95  buf = malloc(len + 1);
96 
97  nread = 0;
98  while (len - nread > 0)
99  {
100  nbytes = lo_read(conn, lobj_fd, buf, len - nread);
101  buf[nbytes] = '\0';
102  fprintf(stderr, ">>> %s", buf);
103  nread += nbytes;
104  if (nbytes <= 0)
105  break; /* no more data? */
106  }
107  free(buf);
108  fprintf(stderr, "\n");
109  lo_close(conn, lobj_fd);
110 }
111 
112 static void
114 {
115  int lobj_fd;
116  char *buf;
117  int nbytes;
118  int nwritten;
119  int i;
120 
121  lobj_fd = lo_open(conn, lobjId, INV_WRITE);
122  if (lobj_fd < 0)
123  fprintf(stderr, "cannot open large object %u", lobjId);
124 
125  if (lo_lseek64(conn, lobj_fd, start, SEEK_SET) < 0)
126  fprintf(stderr, "error in lo_lseek64: %s", PQerrorMessage(conn));
127 
128  buf = malloc(len + 1);
129 
130  for (i = 0; i < len; i++)
131  buf[i] = 'X';
132  buf[i] = '\0';
133 
134  nwritten = 0;
135  while (len - nwritten > 0)
136  {
137  nbytes = lo_write(conn, lobj_fd, buf + nwritten, len - nwritten);
138  nwritten += nbytes;
139  if (nbytes <= 0)
140  {
141  fprintf(stderr, "\nWRITE FAILED!\n");
142  break;
143  }
144  }
145  free(buf);
146  fprintf(stderr, "\n");
147  lo_close(conn, lobj_fd);
148 }
149 
150 static void
152 {
153  int lobj_fd;
154 
155  lobj_fd = lo_open(conn, lobjId, INV_READ | INV_WRITE);
156  if (lobj_fd < 0)
157  fprintf(stderr, "cannot open large object %u", lobjId);
158 
159  if (lo_truncate64(conn, lobj_fd, len) < 0)
160  fprintf(stderr, "error in lo_truncate64: %s", PQerrorMessage(conn));
161 
162  lo_close(conn, lobj_fd);
163 }
164 
165 
166 /*
167  * exportFile -
168  * export large object "lobjOid" to file "out_filename"
169  *
170  */
171 static void
173 {
174  int lobj_fd;
175  char buf[BUFSIZE];
176  int nbytes,
177  tmp;
178  int fd;
179 
180  /*
181  * open the large object
182  */
183  lobj_fd = lo_open(conn, lobjId, INV_READ);
184  if (lobj_fd < 0)
185  fprintf(stderr, "cannot open large object %u", lobjId);
186 
187  /*
188  * open the file to be written to
189  */
190  fd = open(filename, O_CREAT | O_WRONLY | O_TRUNC, 0666);
191  if (fd < 0)
192  { /* error */
193  fprintf(stderr, "cannot open unix file\"%s\"",
194  filename);
195  }
196 
197  /*
198  * read in from the inversion file and write to the Unix file
199  */
200  while ((nbytes = lo_read(conn, lobj_fd, buf, BUFSIZE)) > 0)
201  {
202  tmp = write(fd, buf, nbytes);
203  if (tmp < nbytes)
204  {
205  fprintf(stderr, "error while writing \"%s\"",
206  filename);
207  }
208  }
209 
210  lo_close(conn, lobj_fd);
211  close(fd);
212 }
213 
214 static void
216 {
217  PQfinish(conn);
218  exit(1);
219 }
220 
221 int
222 main(int argc, char **argv)
223 {
224  char *in_filename,
225  *out_filename,
226  *out_filename2;
227  char *database;
228  Oid lobjOid;
229  PGconn *conn;
230  PGresult *res;
231 
232  if (argc != 5)
233  {
234  fprintf(stderr, "Usage: %s database_name in_filename out_filename out_filename2\n",
235  argv[0]);
236  exit(1);
237  }
238 
239  database = argv[1];
240  in_filename = argv[2];
241  out_filename = argv[3];
242  out_filename2 = argv[4];
243 
244  /*
245  * set up the connection
246  */
247  conn = PQsetdb(NULL, NULL, NULL, NULL, database);
248 
249  /* check to see that the backend connection was successfully made */
250  if (PQstatus(conn) != CONNECTION_OK)
251  {
252  fprintf(stderr, "%s", PQerrorMessage(conn));
253  exit_nicely(conn);
254  }
255 
256  /* Set always-secure search path, so malicious users can't take control. */
257  res = PQexec(conn,
258  "SELECT pg_catalog.set_config('search_path', '', false)");
260  {
261  fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
262  PQclear(res);
263  exit_nicely(conn);
264  }
265  PQclear(res);
266 
267  res = PQexec(conn, "begin");
268  PQclear(res);
269  printf("importing file \"%s\" ...\n", in_filename);
270 /* lobjOid = importFile(conn, in_filename); */
271  lobjOid = lo_import(conn, in_filename);
272  if (lobjOid == 0)
273  fprintf(stderr, "%s\n", PQerrorMessage(conn));
274  else
275  {
276  printf("\tas large object %u.\n", lobjOid);
277 
278  printf("picking out bytes 4294967000-4294968000 of the large object\n");
279  pickout(conn, lobjOid, 4294967000U, 1000);
280 
281  printf("overwriting bytes 4294967000-4294968000 of the large object with X's\n");
282  overwrite(conn, lobjOid, 4294967000U, 1000);
283 
284  printf("exporting large object to file \"%s\" ...\n", out_filename);
285 /* exportFile(conn, lobjOid, out_filename); */
286  if (lo_export(conn, lobjOid, out_filename) < 0)
287  fprintf(stderr, "%s\n", PQerrorMessage(conn));
288 
289  printf("truncating to 3294968000 bytes\n");
290  my_truncate(conn, lobjOid, 3294968000U);
291 
292  printf("exporting truncated large object to file \"%s\" ...\n", out_filename2);
293  if (lo_export(conn, lobjOid, out_filename2) < 0)
294  fprintf(stderr, "%s\n", PQerrorMessage(conn));
295  }
296 
297  res = PQexec(conn, "end");
298  PQclear(res);
299  PQfinish(conn);
300  return 0;
301 }
int lo_write(int fd, const char *buf, int len)
Definition: be-fsstubs.c:182
int lo_read(int fd, char *buf, int len)
Definition: be-fsstubs.c:154
char * PQerrorMessage(const PGconn *conn)
Definition: fe-connect.c:7200
ConnStatusType PQstatus(const PGconn *conn)
Definition: fe-connect.c:7137
void PQfinish(PGconn *conn)
Definition: fe-connect.c:4879
ExecStatusType PQresultStatus(const PGresult *res)
Definition: fe-exec.c:3411
PGresult * PQexec(PGconn *conn, const char *query)
Definition: fe-exec.c:2262
int lo_close(PGconn *conn, int fd)
Definition: fe-lobj.c:96
pg_int64 lo_tell64(PGconn *conn, int fd)
Definition: fe-lobj.c:548
Oid lo_creat(PGconn *conn, int mode)
Definition: fe-lobj.c:438
pg_int64 lo_lseek64(PGconn *conn, int fd, pg_int64 offset, int whence)
Definition: fe-lobj.c:385
int lo_open(PGconn *conn, Oid lobjId, int mode)
Definition: fe-lobj.c:57
Oid lo_import(PGconn *conn, const char *filename)
Definition: fe-lobj.c:626
int lo_export(PGconn *conn, Oid lobjId, const char *filename)
Definition: fe-lobj.c:748
int lo_truncate64(PGconn *conn, int fd, pg_int64 len)
Definition: fe-lobj.c:195
return str start
#define free(a)
Definition: header.h:65
#define malloc(a)
Definition: header.h:50
#define close(a)
Definition: win32.h:12
#define write(a, b, c)
Definition: win32.h:14
#define read(a, b, c)
Definition: win32.h:13
int i
Definition: isn.c:72
@ CONNECTION_OK
Definition: libpq-fe.h:81
@ PGRES_TUPLES_OK
Definition: libpq-fe.h:123
#define PQsetdb(M_PGHOST, M_PGPORT, M_PGOPT, M_PGTTY, M_DBNAME)
Definition: libpq-fe.h:327
#define INV_READ
Definition: libpq-fs.h:22
#define INV_WRITE
Definition: libpq-fs.h:21
exit(1)
const void size_t len
static char * filename
Definition: pg_dumpall.c:119
static char * buf
Definition: pg_test_fsync.c:72
#define fprintf
Definition: port.h:242
#define printf(...)
Definition: port.h:244
unsigned int Oid
Definition: postgres_ext.h:31
int64_t pg_int64
Definition: postgres_ext.h:47
static int fd(const char *x, int i)
Definition: preproc-init.c:105
PGconn * conn
Definition: streamutil.c:53
static void overwrite(PGconn *conn, Oid lobjId, pg_int64 start, int len)
Definition: testlo64.c:113
static void exit_nicely(PGconn *conn)
Definition: testlo64.c:215
int main(int argc, char **argv)
Definition: testlo64.c:222
static void pickout(PGconn *conn, Oid lobjId, pg_int64 start, int len)
Definition: testlo64.c:78
static void exportFile(PGconn *conn, Oid lobjId, char *filename)
Definition: testlo64.c:172
static void my_truncate(PGconn *conn, Oid lobjId, pg_int64 len)
Definition: testlo64.c:151
#define BUFSIZE
Definition: testlo64.c:26
static Oid importFile(PGconn *conn, char *filename)
Definition: testlo64.c:34