| 1 | /* |
| 2 | * Copyright (C) 2009 Pierre-Marc Fournier |
| 3 | * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 4 | * |
| 5 | * This library is free software; you can redistribute it and/or |
| 6 | * modify it under the terms of the GNU Lesser General Public |
| 7 | * License as published by the Free Software Foundation; either |
| 8 | * version 2.1 of the License, or (at your option) any later version. |
| 9 | * |
| 10 | * This library is distributed in the hope that it will be useful, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | * Lesser General Public License for more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU Lesser General Public |
| 16 | * License along with this library; if not, write to the Free Software |
| 17 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 18 | */ |
| 19 | |
| 20 | #include <stddef.h> |
| 21 | |
| 22 | /* write() */ |
| 23 | #include <unistd.h> |
| 24 | |
| 25 | /* writev() */ |
| 26 | #include <sys/uio.h> |
| 27 | |
| 28 | /* send() */ |
| 29 | #include <sys/types.h> |
| 30 | #include <sys/socket.h> |
| 31 | |
| 32 | #include <errno.h> |
| 33 | |
| 34 | #include <share.h> |
| 35 | |
| 36 | /* |
| 37 | * This write is patient because it restarts if it was incomplete. |
| 38 | */ |
| 39 | |
| 40 | ssize_t patient_write(int fd, const void *buf, size_t count) |
| 41 | { |
| 42 | const char *bufc = (const char *) buf; |
| 43 | int result; |
| 44 | |
| 45 | for(;;) { |
| 46 | result = write(fd, bufc, count); |
| 47 | if (result == -1 && errno == EINTR) { |
| 48 | continue; |
| 49 | } |
| 50 | if (result <= 0) { |
| 51 | return result; |
| 52 | } |
| 53 | count -= result; |
| 54 | bufc += result; |
| 55 | |
| 56 | if (count == 0) { |
| 57 | break; |
| 58 | } |
| 59 | } |
| 60 | |
| 61 | return bufc-(const char *)buf; |
| 62 | } |
| 63 | |
| 64 | /* |
| 65 | * The `struct iovec *iov` is not `const` because we modify it to support |
| 66 | * partial writes. |
| 67 | */ |
| 68 | ssize_t patient_writev(int fd, struct iovec *iov, int iovcnt) |
| 69 | { |
| 70 | ssize_t written, total_written = 0; |
| 71 | int curr_element_idx = 0; |
| 72 | |
| 73 | for(;;) { |
| 74 | written = writev(fd, iov + curr_element_idx, |
| 75 | iovcnt - curr_element_idx); |
| 76 | if (written == -1 && errno == EINTR) { |
| 77 | continue; |
| 78 | } |
| 79 | if (written <= 0) { |
| 80 | return written; |
| 81 | } |
| 82 | |
| 83 | total_written += written; |
| 84 | |
| 85 | /* |
| 86 | * If it's not the last element in the vector and we have |
| 87 | * written more than the current element size, then increment |
| 88 | * the current element index until we reach the element that |
| 89 | * was partially written. |
| 90 | */ |
| 91 | while (curr_element_idx < iovcnt && |
| 92 | written >= iov[curr_element_idx].iov_len) { |
| 93 | written -= iov[curr_element_idx].iov_len; |
| 94 | curr_element_idx++; |
| 95 | } |
| 96 | |
| 97 | /* Maybe we are done. */ |
| 98 | if (curr_element_idx >= iovcnt) { |
| 99 | break; |
| 100 | } |
| 101 | |
| 102 | /* Update the current element base and size. */ |
| 103 | iov[curr_element_idx].iov_base += written; |
| 104 | iov[curr_element_idx].iov_len -= written; |
| 105 | } |
| 106 | |
| 107 | return total_written; |
| 108 | } |
| 109 | |
| 110 | ssize_t patient_send(int fd, const void *buf, size_t count, int flags) |
| 111 | { |
| 112 | const char *bufc = (const char *) buf; |
| 113 | int result; |
| 114 | |
| 115 | for(;;) { |
| 116 | result = send(fd, bufc, count, flags); |
| 117 | if (result == -1 && errno == EINTR) { |
| 118 | continue; |
| 119 | } |
| 120 | if (result <= 0) { |
| 121 | return result; |
| 122 | } |
| 123 | count -= result; |
| 124 | bufc += result; |
| 125 | |
| 126 | if (count == 0) { |
| 127 | break; |
| 128 | } |
| 129 | } |
| 130 | |
| 131 | return bufc - (const char *) buf; |
| 132 | } |