tools/perf/util/data.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/compiler.h>
   3 #include <linux/kernel.h>
   4 #include <sys/types.h>
   5 #include <sys/stat.h>
   6 #include <errno.h>
   7 #include <fcntl.h>
   8 #include <unistd.h>
   9 #include <string.h>
  10 #include <asm/bug.h>
  11 #include <sys/types.h>
  12 #include <dirent.h>
  13
  14 #include "data.h"
  15 #include "util.h"
  16 #include "debug.h"
  17 #include "header.h"
  18
  19 static void close_dir(struct perf_data_file *files, int nr)
  20 {
  21         while (--nr >= 1) {
  22                 close(files[nr].fd);
  23                 free(files[nr].path);
  24         }
  25         free(files);
  26 }
  27
  28 void perf_data__close_dir(struct perf_data *data)
  29 {
  30         close_dir(data->dir.files, data->dir.nr);
  31 }
  32
  33 int perf_data__create_dir(struct perf_data *data, int nr)
  34 {
  35         struct perf_data_file *files = NULL;
  36         int i, ret = -1;
  37
  38         if (WARN_ON(!data->is_dir))
  39                 return -EINVAL;
  40
  41         files = zalloc(nr * sizeof(*files));
  42         if (!files)
  43                 return -ENOMEM;
  44
  45         data->dir.version = PERF_DIR_VERSION;
  46         data->dir.files   = files;
  47         data->dir.nr      = nr;
  48
  49         for (i = 0; i < nr; i++) {
  50                 struct perf_data_file *file = &files[i];
  51
  52                 if (asprintf(&file->path, "%s/data.%d", data->path, i) < 0)
  53                         goto out_err;
  54
  55                 ret = open(file->path, O_RDWR|O_CREAT|O_TRUNC, S_IRUSR|S_IWUSR);
  56                 if (ret < 0)
  57                         goto out_err;
  58
  59                 file->fd = ret;
  60         }
  61
  62         return 0;
  63
  64 out_err:
  65         close_dir(files, i);
  66         return ret;
  67 }
  68
  69 int perf_data__open_dir(struct perf_data *data)
  70 {
  71         struct perf_data_file *files = NULL;
  72         struct dirent *dent;
  73         int ret = -1;
  74         DIR *dir;
  75         int nr = 0;
  76
  77         if (WARN_ON(!data->is_dir))
  78                 return -EINVAL;
  79
  80         /* The version is provided by DIR_FORMAT feature. */
  81         if (WARN_ON(data->dir.version != PERF_DIR_VERSION))
  82                 return -1;
  83
  84         dir = opendir(data->path);
  85         if (!dir)
  86                 return -EINVAL;
  87
  88         while ((dent = readdir(dir)) != NULL) {
  89                 struct perf_data_file *file;
  90                 char path[PATH_MAX];
  91                 struct stat st;
  92
  93                 snprintf(path, sizeof(path), "%s/%s", data->path, dent->d_name);
  94                 if (stat(path, &st))
  95                         continue;
  96
  97                 if (!S_ISREG(st.st_mode) || strncmp(dent->d_name, "data", 4))
  98                         continue;
  99
 100                 ret = -ENOMEM;
 101
 102                 file = realloc(files, (nr + 1) * sizeof(*files));
 103                 if (!file)
 104                         goto out_err;
 105
 106                 files = file;
 107                 file = &files[nr++];
 108
 109                 file->path = strdup(path);
 110                 if (!file->path)
 111                         goto out_err;
 112
 113                 ret = open(file->path, O_RDONLY);
 114                 if (ret < 0)
 115                         goto out_err;
 116
 117                 file->fd = ret;
 118                 file->size = st.st_size;
 119         }
 120
 121         if (!files)
 122                 return -EINVAL;
 123
 124         data->dir.files = files;
 125         data->dir.nr    = nr;
 126         return 0;
 127
 128 out_err:
 129         close_dir(files, nr);
 130         return ret;
 131 }
 132
 133 int perf_data__update_dir(struct perf_data *data)
 134 {
 135         int i;
 136
 137         if (WARN_ON(!data->is_dir))
 138                 return -EINVAL;
 139
 140         for (i = 0; i < data->dir.nr; i++) {
 141                 struct perf_data_file *file = &data->dir.files[i];
 142                 struct stat st;
 143
 144                 if (fstat(file->fd, &st))
 145                         return -1;
 146
 147                 file->size = st.st_size;
 148         }
 149
 150         return 0;
 151 }
 152
 153 static bool check_pipe(struct perf_data *data)
 154 {
 155         struct stat st;
 156         bool is_pipe = false;
 157         int fd = perf_data__is_read(data) ?
 158                  STDIN_FILENO : STDOUT_FILENO;
 159
 160         if (!data->path) {
 161                 if (!fstat(fd, &st) && S_ISFIFO(st.st_mode))
 162                         is_pipe = true;
 163         } else {
 164                 if (!strcmp(data->path, "-"))
 165                         is_pipe = true;
 166         }
 167
 168         if (is_pipe)
 169                 data->file.fd = fd;
 170
 171         return data->is_pipe = is_pipe;
 172 }
 173
 174 static int check_backup(struct perf_data *data)
 175 {
 176         struct stat st;
 177
 178         if (perf_data__is_read(data))
 179                 return 0;
 180
 181         if (!stat(data->path, &st) && st.st_size) {
 182                 char oldname[PATH_MAX];
 183                 int ret;
 184
 185                 snprintf(oldname, sizeof(oldname), "%s.old",
 186                          data->path);
 187
 188                 ret = rm_rf_perf_data(oldname);
 189                 if (ret) {
 190                         pr_err("Can't remove old data: %s (%s)\n",
 191                                ret == -2 ?
 192                                "Unknown file found" : strerror(errno),
 193                                oldname);
 194                         return -1;
 195                 }
 196
 197                 if (rename(data->path, oldname)) {
 198                         pr_err("Can't move data: %s (%s to %s)\n",
 199                                strerror(errno),
 200                                data->path, oldname);
 201                         return -1;
 202                 }
 203         }
 204
 205         return 0;
 206 }
 207
 208 static bool is_dir(struct perf_data *data)
 209 {
 210         struct stat st;
 211
 212         if (stat(data->path, &st))
 213                 return false;
 214
 215         return (st.st_mode & S_IFMT) == S_IFDIR;
 216 }
 217
 218 static int open_file_read(struct perf_data *data)
 219 {
 220         struct stat st;
 221         int fd;
 222         char sbuf[STRERR_BUFSIZE];
 223
 224         fd = open(data->file.path, O_RDONLY);
 225         if (fd < 0) {
 226                 int err = errno;
 227
 228                 pr_err("failed to open %s: %s", data->file.path,
 229                         str_error_r(err, sbuf, sizeof(sbuf)));
 230                 if (err == ENOENT && !strcmp(data->file.path, "perf.data"))
 231                         pr_err("  (try 'perf record' first)");
 232                 pr_err("\n");
 233                 return -err;
 234         }
 235
 236         if (fstat(fd, &st) < 0)
 237                 goto out_close;
 238
 239         if (!data->force && st.st_uid && (st.st_uid != geteuid())) {
 240                 pr_err("File %s not owned by current user or root (use -f to override)\n",
 241                        data->file.path);
 242                 goto out_close;
 243         }
 244
 245         if (!st.st_size) {
 246                 pr_info("zero-sized data (%s), nothing to do!\n",
 247                         data->file.path);
 248                 goto out_close;
 249         }
 250
 251         data->file.size = st.st_size;
 252         return fd;
 253
 254  out_close:
 255         close(fd);
 256         return -1;
 257 }
 258
 259 static int open_file_write(struct perf_data *data)
 260 {
 261         int fd;
 262         char sbuf[STRERR_BUFSIZE];
 263
 264         fd = open(data->file.path, O_CREAT|O_RDWR|O_TRUNC|O_CLOEXEC,
 265                   S_IRUSR|S_IWUSR);
 266
 267         if (fd < 0)
 268                 pr_err("failed to open %s : %s\n", data->file.path,
 269                         str_error_r(errno, sbuf, sizeof(sbuf)));
 270
 271         return fd;
 272 }
 273
 274 static int open_file(struct perf_data *data)
 275 {
 276         int fd;
 277
 278         fd = perf_data__is_read(data) ?
 279              open_file_read(data) : open_file_write(data);
 280
 281         if (fd < 0) {
 282                 zfree(&data->file.path);
 283                 return -1;
 284         }
 285
 286         data->file.fd = fd;
 287         return 0;
 288 }
 289
 290 static int open_file_dup(struct perf_data *data)
 291 {
 292         data->file.path = strdup(data->path);
 293         if (!data->file.path)
 294                 return -ENOMEM;
 295
 296         return open_file(data);
 297 }
 298
 299 static int open_dir(struct perf_data *data)
 300 {
 301         int ret;
 302
 303         /*
 304          * So far we open only the header, so we can read the data version and
 305          * layout.
 306          */
 307         if (asprintf(&data->file.path, "%s/header", data->path) < 0)
 308                 return -1;
 309
 310         if (perf_data__is_write(data) &&
 311             mkdir(data->path, S_IRWXU) < 0)
 312                 return -1;
 313
 314         ret = open_file(data);
 315
 316         /* Cleanup whatever we managed to create so far. */
 317         if (ret && perf_data__is_write(data))
 318                 rm_rf_perf_data(data->path);
 319
 320         return ret;
 321 }
 322
 323 int perf_data__open(struct perf_data *data)
 324 {
 325         if (check_pipe(data))
 326                 return 0;
 327
 328         if (!data->path)
 329                 data->path = "perf.data";
 330
 331         if (check_backup(data))
 332                 return -1;
 333
 334         if (perf_data__is_read(data))
 335                 data->is_dir = is_dir(data);
 336
 337         return perf_data__is_dir(data) ?
 338                open_dir(data) : open_file_dup(data);
 339 }
 340
 341 void perf_data__close(struct perf_data *data)
 342 {
 343         if (perf_data__is_dir(data))
 344                 perf_data__close_dir(data);
 345
 346         zfree(&data->file.path);
 347         close(data->file.fd);
 348 }
 349
 350 ssize_t perf_data_file__write(struct perf_data_file *file,
 351                               void *buf, size_t size)
 352 {
 353         return writen(file->fd, buf, size);
 354 }
 355
 356 ssize_t perf_data__write(struct perf_data *data,
 357                               void *buf, size_t size)
 358 {
 359         return perf_data_file__write(&data->file, buf, size);
 360 }
 361
 362 int perf_data__switch(struct perf_data *data,
 363                            const char *postfix,
 364                            size_t pos, bool at_exit,
 365                            char **new_filepath)
 366 {
 367         int ret;
 368
 369         if (check_pipe(data))
 370                 return -EINVAL;
 371         if (perf_data__is_read(data))
 372                 return -EINVAL;
 373
 374         if (asprintf(new_filepath, "%s.%s", data->path, postfix) < 0)
 375                 return -ENOMEM;
 376
 377         /*
 378          * Only fire a warning, don't return error, continue fill
 379          * original file.
 380          */
 381         if (rename(data->path, *new_filepath))
 382                 pr_warning("Failed to rename %s to %s\n", data->path, *new_filepath);
 383
 384         if (!at_exit) {
 385                 close(data->file.fd);
 386                 ret = perf_data__open(data);
 387                 if (ret < 0)
 388                         goto out;
 389
 390                 if (lseek(data->file.fd, pos, SEEK_SET) == (off_t)-1) {
 391                         ret = -errno;
 392                         pr_debug("Failed to lseek to %zu: %s",
 393                                  pos, strerror(errno));
 394                         goto out;
 395                 }
 396         }
 397         ret = data->file.fd;
 398 out:
 399         return ret;
 400 }
 401
 402 unsigned long perf_data__size(struct perf_data *data)
 403 {
 404         u64 size = data->file.size;
 405         int i;
 406
 407         if (!data->is_dir)
 408                 return size;
 409
 410         for (i = 0; i < data->dir.nr; i++) {
 411                 struct perf_data_file *file = &data->dir.files[i];
 412
 413                 size += file->size;
 414         }
 415
 416         return size;
 417 }