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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 | // SPDX-License-Identifier: GPL-2.0 #include <linux/compiler.h> #include <linux/kernel.h> #include <sys/types.h> #include <sys/stat.h> #include <errno.h> #include <unistd.h> #include <string.h> #include "data.h" #include "util.h" #include "debug.h" #ifndef O_CLOEXEC #ifdef __sparc__ #define O_CLOEXEC 0x400000 #elif defined(__alpha__) || defined(__hppa__) #define O_CLOEXEC 010000000 #else #define O_CLOEXEC 02000000 #endif #endif static bool check_pipe(struct perf_data_file *file) { struct stat st; bool is_pipe = false; int fd = perf_data_file__is_read(file) ? STDIN_FILENO : STDOUT_FILENO; if (!file->path) { if (!fstat(fd, &st) && S_ISFIFO(st.st_mode)) is_pipe = true; } else { if (!strcmp(file->path, "-")) is_pipe = true; } if (is_pipe) file->fd = fd; return file->is_pipe = is_pipe; } static int check_backup(struct perf_data_file *file) { struct stat st; if (!stat(file->path, &st) && st.st_size) { /* TODO check errors properly */ char oldname[PATH_MAX]; snprintf(oldname, sizeof(oldname), "%s.old", file->path); unlink(oldname); rename(file->path, oldname); } return 0; } static int open_file_read(struct perf_data_file *file) { struct stat st; int fd; char sbuf[STRERR_BUFSIZE]; fd = open(file->path, O_RDONLY); if (fd < 0) { int err = errno; pr_err("failed to open %s: %s", file->path, str_error_r(err, sbuf, sizeof(sbuf))); if (err == ENOENT && !strcmp(file->path, "perf.data")) pr_err(" (try 'perf record' first)"); pr_err("\n"); return -err; } if (fstat(fd, &st) < 0) goto out_close; if (!file->force && st.st_uid && (st.st_uid != geteuid())) { pr_err("File %s not owned by current user or root (use -f to override)\n", file->path); goto out_close; } if (!st.st_size) { pr_info("zero-sized file (%s), nothing to do!\n", file->path); goto out_close; } file->size = st.st_size; return fd; out_close: close(fd); return -1; } static int open_file_write(struct perf_data_file *file) { int fd; char sbuf[STRERR_BUFSIZE]; if (check_backup(file)) return -1; fd = open(file->path, O_CREAT|O_RDWR|O_TRUNC|O_CLOEXEC, S_IRUSR|S_IWUSR); if (fd < 0) pr_err("failed to open %s : %s\n", file->path, str_error_r(errno, sbuf, sizeof(sbuf))); return fd; } static int open_file(struct perf_data_file *file) { int fd; fd = perf_data_file__is_read(file) ? open_file_read(file) : open_file_write(file); file->fd = fd; return fd < 0 ? -1 : 0; } int perf_data_file__open(struct perf_data_file *file) { if (check_pipe(file)) return 0; if (!file->path) file->path = "perf.data"; return open_file(file); } void perf_data_file__close(struct perf_data_file *file) { close(file->fd); } ssize_t perf_data_file__write(struct perf_data_file *file, void *buf, size_t size) { return writen(file->fd, buf, size); } int perf_data_file__switch(struct perf_data_file *file, const char *postfix, size_t pos, bool at_exit) { char *new_filepath; int ret; if (check_pipe(file)) return -EINVAL; if (perf_data_file__is_read(file)) return -EINVAL; if (asprintf(&new_filepath, "%s.%s", file->path, postfix) < 0) return -ENOMEM; /* * Only fire a warning, don't return error, continue fill * original file. */ if (rename(file->path, new_filepath)) pr_warning("Failed to rename %s to %s\n", file->path, new_filepath); if (!at_exit) { close(file->fd); ret = perf_data_file__open(file); if (ret < 0) goto out; if (lseek(file->fd, pos, SEEK_SET) == (off_t)-1) { ret = -errno; pr_debug("Failed to lseek to %zu: %s", pos, strerror(errno)); goto out; } } ret = file->fd; out: free(new_filepath); return ret; } |