projects / lttng-ust.git / blame
| Commit | Line | Data |
|---|---|---|
| f6da3aa6 | 1 | /* |
| c0c0989a | 2 | * SPDX-License-Identifier: LGPL-2.1-or-later |
| f6da3aa6 | 3 | * |
| c0c0989a MJ |
4 | * Copyright (C) 2009 Pierre-Marc Fournier |
| 5 | * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
| f6da3aa6 MD |
6 | */ |
| 7 | ||
| b4051ad8 FD |
8 | #include <stddef.h> |
| 9 | ||
| f6da3aa6 MD |
10 | /* write() */ |
| 11 | #include <unistd.h> | |
| 12 | ||
| 9fe043d7 FD |
13 | /* writev() */ |
| 14 | #include <sys/uio.h> | |
| 15 | ||
| f6da3aa6 MD |
16 | /* send() */ |
| 17 | #include <sys/types.h> | |
| 18 | #include <sys/socket.h> | |
| 19 | ||
| 20 | #include <errno.h> | |
| 21 | ||
| 864a1eda | 22 | #include <ust-share.h> |
| f6da3aa6 MD |
23 | |
| 24 | /* | |
| 25 | * This write is patient because it restarts if it was incomplete. | |
| 26 | */ | |
| 27 | ||
| 28 | ssize_t patient_write(int fd, const void *buf, size_t count) | |
| 29 | { | |
| 30 | const char *bufc = (const char *) buf; | |
| 31 | int result; | |
| 32 | ||
| 33 | for(;;) { | |
| 34 | result = write(fd, bufc, count); | |
| 35 | if (result == -1 && errno == EINTR) { | |
| 36 | continue; | |
| 37 | } | |
| 38 | if (result <= 0) { | |
| 39 | return result; | |
| 40 | } | |
| 41 | count -= result; | |
| 42 | bufc += result; | |
| 43 | ||
| 44 | if (count == 0) { | |
| 45 | break; | |
| 46 | } | |
| 47 | } | |
| 48 | ||
| 49 | return bufc-(const char *)buf; | |
| 50 | } | |
| 51 | ||
| 9fe043d7 FD |
52 | /* |
| 53 | * The `struct iovec *iov` is not `const` because we modify it to support | |
| 54 | * partial writes. | |
| 55 | */ | |
| 56 | ssize_t patient_writev(int fd, struct iovec *iov, int iovcnt) | |
| 57 | { | |
| 58 | ssize_t written, total_written = 0; | |
| 59 | int curr_element_idx = 0; | |
| 60 | ||
| 61 | for(;;) { | |
| 62 | written = writev(fd, iov + curr_element_idx, | |
| 63 | iovcnt - curr_element_idx); | |
| 64 | if (written == -1 && errno == EINTR) { | |
| 65 | continue; | |
| 66 | } | |
| 67 | if (written <= 0) { | |
| 68 | return written; | |
| 69 | } | |
| 70 | ||
| 71 | total_written += written; | |
| 72 | ||
| 73 | /* | |
| 74 | * If it's not the last element in the vector and we have | |
| 75 | * written more than the current element size, then increment | |
| 76 | * the current element index until we reach the element that | |
| 77 | * was partially written. | |
| 78 | */ | |
| 79 | while (curr_element_idx < iovcnt && | |
| 80 | written >= iov[curr_element_idx].iov_len) { | |
| 81 | written -= iov[curr_element_idx].iov_len; | |
| 82 | curr_element_idx++; | |
| 83 | } | |
| 84 | ||
| 85 | /* Maybe we are done. */ | |
| 86 | if (curr_element_idx >= iovcnt) { | |
| 87 | break; | |
| 88 | } | |
| 89 | ||
| 90 | /* Update the current element base and size. */ | |
| 91 | iov[curr_element_idx].iov_base += written; | |
| 92 | iov[curr_element_idx].iov_len -= written; | |
| 93 | } | |
| 94 | ||
| 95 | return total_written; | |
| 96 | } | |
| 97 | ||
| f6da3aa6 MD |
98 | ssize_t patient_send(int fd, const void *buf, size_t count, int flags) |
| 99 | { | |
| 100 | const char *bufc = (const char *) buf; | |
| 101 | int result; | |
| 102 | ||
| 103 | for(;;) { | |
| 104 | result = send(fd, bufc, count, flags); | |
| 105 | if (result == -1 && errno == EINTR) { | |
| 106 | continue; | |
| 107 | } | |
| 108 | if (result <= 0) { | |
| 109 | return result; | |
| 110 | } | |
| 111 | count -= result; | |
| 112 | bufc += result; | |
| 113 | ||
| 114 | if (count == 0) { | |
| 115 | break; | |
| 116 | } | |
| 117 | } | |
| 118 | ||
| 119 | return bufc - (const char *) buf; | |
| 120 | } |