diff options
| -rw-r--r-- | lib/libc/stdio/getdelim.c | 27 | ||||
| -rw-r--r-- | lib/libc/tests/stdio/getdelim_test.c | 199 |
2 files changed, 223 insertions, 3 deletions
diff --git a/lib/libc/stdio/getdelim.c b/lib/libc/stdio/getdelim.c index 8d8414266c78..ad1439ed071f 100644 --- a/lib/libc/stdio/getdelim.c +++ b/lib/libc/stdio/getdelim.c @@ -2,6 +2,7 @@ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2009 David Schultz <das@FreeBSD.org> + * Copyright (c) 2021 Dell EMC * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -138,10 +139,30 @@ getdelim(char ** __restrict linep, size_t * __restrict linecapp, int delim, while ((endp = memchr(fp->_p, delim, fp->_r)) == NULL) { if (sappend(linep, &linelen, linecapp, fp->_p, fp->_r)) goto error; + errno = 0; if (__srefill(fp)) { - if (!__sfeof(fp)) - goto error; - goto done; /* hit EOF */ + if (__sfeof(fp)) + goto done; + if (errno == EAGAIN) { + /* + * We need to undo a partial read that has + * been placed into linep or we would otherwise + * lose it on the next read. + */ + while (linelen > 0) { + if (__ungetc((*linep)[--linelen], + fp) == EOF) + goto error; + } + /* + * This is not strictly needed but it is + * possible a consumer has worked around an + * older EAGAIN bug by buffering a partial + * return. + */ + (*linep)[0] = '\0'; + } + goto error; } } endp++; /* snarf the delimiter, too */ diff --git a/lib/libc/tests/stdio/getdelim_test.c b/lib/libc/tests/stdio/getdelim_test.c index 8dc662fcab8f..7b20b02a36f1 100644 --- a/lib/libc/tests/stdio/getdelim_test.c +++ b/lib/libc/tests/stdio/getdelim_test.c @@ -1,5 +1,6 @@ /*- * Copyright (c) 2009 David Schultz <das@FreeBSD.org> + * Copyright (c) 2021 Dell EMC * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -27,6 +28,12 @@ #include <sys/cdefs.h> __FBSDID("$FreeBSD$"); +#include <sys/param.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/wait.h> + +#include <fcntl.h> #include <errno.h> #include <stdio.h> #include <stdlib.h> @@ -221,6 +228,196 @@ ATF_TC_BODY(empty_NULL_buffer, tc) fclose(fp); } +static void +_ipc_read(int fd, char wait_c) +{ + char c; + ssize_t len; + + c = 0; + while (c != wait_c) { + len = read(fd, &c, 1); + ATF_CHECK_MSG(len != 0, + "EOF on IPC pipe while waiting. Did other side fail?"); + ATF_CHECK_MSG(len == 1 || errno == EINTR, + "read %zu bytes errno %d\n", len, errno); + if (len != 1 || errno != EINTR) + break; + } +} + +static void +_ipc_write(int fd, char c) +{ + + while ((write(fd, &c, 1) != 1)) + ATF_REQUIRE(errno == EINTR); +} + +static void +ipc_wait(int ipcfd[2]) +{ + + _ipc_read(ipcfd[0], '+'); + /* Send ACK. */ + _ipc_write(ipcfd[1], '-'); +} + +static void +ipc_wakeup(int ipcfd[2]) +{ + + _ipc_write(ipcfd[1], '+'); + /* Wait for ACK. */ + _ipc_read(ipcfd[0], '-'); +} + +static void +_nonblock_eagain(int buf_mode) +{ + FILE *fp; + const char delim = '!'; + const char *strs[] = { + "first line partial!", + "second line is sent in full!", + "third line is sent partially!", + "last line is sent in full!", + }; + char *line; + size_t linecap, strslen[nitems(strs)]; + ssize_t linelen; + int fd_fifo, flags, i, ipcfd[2], pipedes[2], pipedes2[2], status; + pid_t pid; + + line = NULL; + linecap = 0; + for (i = 0; i < nitems(strslen); i++) + strslen[i] = strlen(strs[i]); + ATF_REQUIRE(pipe2(pipedes, O_CLOEXEC) == 0); + ATF_REQUIRE(pipe2(pipedes2, O_CLOEXEC) == 0); + + (void)unlink("fifo"); + ATF_REQUIRE(mkfifo("fifo", 0666) == 0); + ATF_REQUIRE((pid = fork()) >= 0); + if (pid == 0) { + close(pipedes[0]); + ipcfd[1] = pipedes[1]; + ipcfd[0] = pipedes2[0]; + close(pipedes2[1]); + + ATF_REQUIRE((fd_fifo = open("fifo", O_WRONLY)) != -1); + + /* Partial write. */ + ATF_REQUIRE(write(fd_fifo, strs[0], strslen[0] - 3) == + strslen[0] - 3); + ipc_wakeup(ipcfd); + + ipc_wait(ipcfd); + /* Finish off the first line. */ + ATF_REQUIRE(write(fd_fifo, + &(strs[0][strslen[0] - 3]), 3) == 3); + /* And include the second full line and a partial 3rd line. */ + ATF_REQUIRE(write(fd_fifo, strs[1], strslen[1]) == strslen[1]); + ATF_REQUIRE(write(fd_fifo, strs[2], strslen[2] - 3) == + strslen[2] - 3); + ipc_wakeup(ipcfd); + + ipc_wait(ipcfd); + /* Finish the partial write and partially send the last. */ + ATF_REQUIRE(write(fd_fifo, + &(strs[2][strslen[2] - 3]), 3) == 3); + ATF_REQUIRE(write(fd_fifo, strs[3], strslen[3] - 3) == + strslen[3] - 3); + ipc_wakeup(ipcfd); + + ipc_wait(ipcfd); + /* Finish the write */ + ATF_REQUIRE(write(fd_fifo, + &(strs[3][strslen[3] - 3]), 3) == 3); + ipc_wakeup(ipcfd); + _exit(0); + } + ipcfd[0] = pipedes[0]; + close(pipedes[1]); + close(pipedes2[0]); + ipcfd[1] = pipedes2[1]; + + ATF_REQUIRE((fp = fopen("fifo", "r")) != NULL); + setvbuf(fp, (char *)NULL, buf_mode, 0); + ATF_REQUIRE((flags = fcntl(fileno(fp), F_GETFL, 0)) != -1); + ATF_REQUIRE(fcntl(fileno(fp), F_SETFL, flags | O_NONBLOCK) >= 0); + + /* Wait until the writer completes its partial write. */ + ipc_wait(ipcfd); + ATF_REQUIRE_ERRNO(EAGAIN, + (linelen = getdelim(&line, &linecap, delim, fp)) == -1); + ATF_REQUIRE_STREQ("", line); + ATF_REQUIRE(ferror(fp)); + ATF_REQUIRE(!feof(fp)); + clearerr(fp); + ipc_wakeup(ipcfd); + + ipc_wait(ipcfd); + /* + * Should now have the finished first line, a full second line, + * and a partial third line. + */ + ATF_CHECK(getdelim(&line, &linecap, delim, fp) == strslen[0]); + ATF_REQUIRE_STREQ(strs[0], line); + ATF_REQUIRE(getdelim(&line, &linecap, delim, fp) == strslen[1]); + ATF_REQUIRE_STREQ(strs[1], line); + + ATF_REQUIRE_ERRNO(EAGAIN, + (linelen = getdelim(&line, &linecap, delim, fp)) == -1); + ATF_REQUIRE_STREQ("", line); + ATF_REQUIRE(ferror(fp)); + ATF_REQUIRE(!feof(fp)); + clearerr(fp); + ipc_wakeup(ipcfd); + + /* Wait for the partial write to be completed and another to be done. */ + ipc_wait(ipcfd); + ATF_REQUIRE((linelen = getdelim(&line, &linecap, delim, fp)) != -1); + ATF_REQUIRE(!ferror(fp)); + ATF_REQUIRE(!feof(fp)); + ATF_REQUIRE_STREQ(strs[2], line); + ATF_REQUIRE(linelen == strslen[2]); + + ATF_REQUIRE_ERRNO(EAGAIN, + (linelen = getdelim(&line, &linecap, delim, fp)) == -1); + ATF_REQUIRE_STREQ("", line); + ATF_REQUIRE(ferror(fp)); + ATF_REQUIRE(!feof(fp)); + clearerr(fp); + ipc_wakeup(ipcfd); + + ipc_wait(ipcfd); + ATF_REQUIRE((linelen = getdelim(&line, &linecap, delim, fp)) != -1); + ATF_REQUIRE(!ferror(fp)); + ATF_REQUIRE(!feof(fp)); + ATF_REQUIRE_STREQ(strs[3], line); + ATF_REQUIRE(linelen == strslen[3]); + + ATF_REQUIRE(waitpid(pid, &status, WEXITED) != -1); + ATF_REQUIRE(WIFEXITED(status)); + ATF_REQUIRE(WEXITSTATUS(status) == 0); +} + +ATF_TC_WITHOUT_HEAD(nonblock_eagain_buffered); +ATF_TC_BODY(nonblock_eagain_buffered, tc) +{ + + _nonblock_eagain(_IOFBF); +} + +ATF_TC_WITHOUT_HEAD(nonblock_eagain_unbuffered); +ATF_TC_BODY(nonblock_eagain_unbuffered, tc) +{ + + _nonblock_eagain(_IONBF); +} + + ATF_TP_ADD_TCS(tp) { @@ -230,6 +427,8 @@ ATF_TP_ADD_TCS(tp) ATF_TP_ADD_TC(tp, invalid_params); ATF_TP_ADD_TC(tp, nul); ATF_TP_ADD_TC(tp, empty_NULL_buffer); + ATF_TP_ADD_TC(tp, nonblock_eagain_unbuffered); + ATF_TP_ADD_TC(tp, nonblock_eagain_buffered); return (atf_no_error()); } |