1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2014, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com> 4 */ 5 #include "array.h" 6 #include <errno.h> 7 #include <fcntl.h> 8 #include <poll.h> 9 #include <stdlib.h> 10 #include <unistd.h> 11 #include <string.h> 12 13 void fdarray__init(struct fdarray *fda, int nr_autogrow) 14 { 15 fda->entries = NULL; 16 fda->priv = NULL; 17 fda->nr = fda->nr_alloc = 0; 18 fda->nr_autogrow = nr_autogrow; 19 } 20 21 int fdarray__grow(struct fdarray *fda, int nr) 22 { 23 struct priv *priv; 24 int nr_alloc = fda->nr_alloc + nr; 25 size_t psize = sizeof(fda->priv[0]) * nr_alloc; 26 size_t size = sizeof(struct pollfd) * nr_alloc; 27 struct pollfd *entries = realloc(fda->entries, size); 28 29 if (entries == NULL) 30 return -ENOMEM; 31 32 priv = realloc(fda->priv, psize); 33 if (priv == NULL) { 34 /* this will be freed by fdarray__exit() */ 35 fda->entries = entries; 36 return -ENOMEM; 37 } 38 39 memset(&entries[fda->nr_alloc], 0, sizeof(struct pollfd) * nr); 40 memset(&priv[fda->nr_alloc], 0, sizeof(fda->priv[0]) * nr); 41 42 fda->nr_alloc = nr_alloc; 43 fda->entries = entries; 44 fda->priv = priv; 45 return 0; 46 } 47 48 struct fdarray *fdarray__new(int nr_alloc, int nr_autogrow) 49 { 50 struct fdarray *fda = calloc(1, sizeof(*fda)); 51 52 if (fda != NULL) { 53 if (fdarray__grow(fda, nr_alloc)) { 54 fdarray__delete(fda); 55 fda = NULL; 56 } else { 57 fda->nr_autogrow = nr_autogrow; 58 } 59 } 60 61 return fda; 62 } 63 64 void fdarray__exit(struct fdarray *fda) 65 { 66 free(fda->entries); 67 free(fda->priv); 68 fdarray__init(fda, 0); 69 } 70 71 void fdarray__delete(struct fdarray *fda) 72 { 73 fdarray__exit(fda); 74 free(fda); 75 } 76 77 int fdarray__add(struct fdarray *fda, int fd, short revents, enum fdarray_flags flags) 78 { 79 int pos = fda->nr; 80 81 if (fda->nr == fda->nr_alloc && 82 fdarray__grow(fda, fda->nr_autogrow) < 0) 83 return -ENOMEM; 84 85 fda->entries[fda->nr].fd = fd; 86 fda->entries[fda->nr].events = revents; 87 fda->priv[fda->nr].flags = flags; 88 fda->nr++; 89 return pos; 90 } 91 92 int fdarray__dup_entry_from(struct fdarray *fda, int pos, struct fdarray *from) 93 { 94 struct pollfd *entry; 95 int npos; 96 97 if (pos >= from->nr) 98 return -EINVAL; 99 100 entry = &from->entries[pos]; 101 102 npos = fdarray__add(fda, entry->fd, entry->events, from->priv[pos].flags); 103 if (npos >= 0) 104 fda->priv[npos] = from->priv[pos]; 105 106 return npos; 107 } 108 109 int fdarray__filter(struct fdarray *fda, short revents, 110 void (*entry_destructor)(struct fdarray *fda, int fd, void *arg), 111 void *arg) 112 { 113 int fd, nr = 0; 114 115 if (fda->nr == 0) 116 return 0; 117 118 for (fd = 0; fd < fda->nr; ++fd) { 119 if (fda->priv[fd].flags & fdarray_flag__nonfilterable) 120 continue; 121 122 if (!fda->entries[fd].events) 123 continue; 124 125 if (fda->entries[fd].revents & revents) { 126 if (entry_destructor) 127 entry_destructor(fda, fd, arg); 128 129 /* 130 * Set fd to -1 so poll() ignores this entry; otherwise 131 * POLLHUP/POLLERR are still reported for events=0 fds 132 * (POSIX: always checked), causing a poll storm. 133 */ 134 fda->entries[fd].fd = -1; 135 fda->entries[fd].revents = fda->entries[fd].events = 0; 136 continue; 137 } 138 139 ++nr; 140 } 141 142 return nr; 143 } 144 145 int fdarray__poll(struct fdarray *fda, int timeout) 146 { 147 return poll(fda->entries, fda->nr, timeout); 148 } 149 150 int fdarray__fprintf(struct fdarray *fda, FILE *fp) 151 { 152 int fd, printed = fprintf(fp, "%d [ ", fda->nr); 153 154 for (fd = 0; fd < fda->nr; ++fd) 155 printed += fprintf(fp, "%s%d", fd ? ", " : "", fda->entries[fd].fd); 156 157 return printed + fprintf(fp, " ]"); 158 } 159