From 83c0aa17b18e738ae581507fb84041165668159c Mon Sep 17 00:00:00 2001 From: Chris Cromer Date: Thu, 22 Jul 2021 22:16:00 -0400 Subject: [PATCH] add stdin redirection and refactor --- src/include/redirect.h | 4 +-- src/loop.c | 59 +++++++++++++++++++++++++++++------------- src/redirect.c | 7 +---- 3 files changed, 43 insertions(+), 27 deletions(-) diff --git a/src/include/redirect.h b/src/include/redirect.h index 77ce6d1..08b8a5f 100644 --- a/src/include/redirect.h +++ b/src/include/redirect.h @@ -12,8 +12,6 @@ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ -#include - #ifndef _MYSHELLIN_REDIRECT #define _MYSHELLIN_REDIRECT @@ -45,7 +43,7 @@ typedef struct { /** * Whether or not to truncate or append the file. */ - bool append; + int flags; } Redirect; /** diff --git a/src/loop.c b/src/loop.c index 25f7f63..dbc8301 100644 --- a/src/loop.c +++ b/src/loop.c @@ -13,6 +13,7 @@ */ #define _GNU_SOURCE +#include #include #include #include @@ -65,43 +66,63 @@ void loop() { StringArray *args = create_string_array(); - enum FileType {FileType_none, FileType_stdout, FileType_stderr}; - enum FileType get_file_name = FileType_none; - Redirect out = {.fd = 1, .fd_new = -1, .fd_copy = -1, .filename = NULL, .append = false}; - Redirect err = {.fd = 2, .fd_new = -1, .fd_copy = -1, .filename = NULL, .append = false}; + int get_file_name = -1; + Redirect in = {.fd = STDIN_FILENO, .fd_new = -1, .fd_copy = -1, .filename = NULL, .flags = O_RDONLY}; + Redirect out = {.fd = STDOUT_FILENO, .fd_new = -1, .fd_copy = -1, .filename = NULL, .flags = O_WRONLY | O_CREAT | O_TRUNC}; + Redirect err = {.fd = STDERR_FILENO, .fd_new = -1, .fd_copy = -1, .filename = NULL, .flags = O_WRONLY | O_CREAT | O_TRUNC}; char *saveptr = NULL; char *token = strtok_r(line, " ", &saveptr); while (token) { - if (get_file_name == FileType_stdout) { + if (get_file_name == STDIN_FILENO) { + // get file name for stdin redirect + set_filename(&in, token); + get_file_name = -1; + } + else if (get_file_name == STDOUT_FILENO) { // get file name for stdout redirect set_filename(&out, token); - get_file_name = FileType_none; + get_file_name = -1; } - else if (get_file_name == 2) { + else if (get_file_name == STDERR_FILENO) { // get file name for stderr redirect set_filename(&err, token); - get_file_name = FileType_none; + get_file_name = -1; } else if (strcmp(token, ">") == 0 || strcmp(token, "1>") == 0) { // redirect stdout and overwrite - get_file_name = FileType_stdout; - out.append = false; + get_file_name = STDOUT_FILENO; + if ((out.flags & O_APPEND) == O_APPEND) { + out.flags &= ~O_APPEND; + out.flags |= O_TRUNC; + } } else if (strcmp(token, ">>") == 0 || strcmp(token, "1>>") == 0) { // redirect stdout and append - get_file_name = FileType_stdout; - out.append = true; + get_file_name = STDOUT_FILENO; + if ((out.flags & O_TRUNC) == O_TRUNC) { + out.flags &= ~O_TRUNC; + out.flags |= O_APPEND; + } } else if (strcmp(token, "2>") == 0) { - // redirect stdout and overwrite - get_file_name = FileType_stderr; - err.append = false; + // redirect stderr and overwrite + get_file_name = STDERR_FILENO; + if ((err.flags & O_APPEND) == O_APPEND) { + err.flags &= ~O_APPEND; + err.flags |= O_TRUNC; + } } else if (strcmp(token, "2>>") == 0) { - // redirect stdout and append - get_file_name = FileType_stderr; - err.append = true; + // redirect stderr and append + get_file_name = STDERR_FILENO; + if ((err.flags & O_TRUNC) == O_TRUNC) { + err.flags &= ~O_TRUNC; + err.flags |= O_APPEND; + } + } + else if (strcmp(token, "<") == 0) { + get_file_name = STDIN_FILENO; } else { insert_string_array(args, token); @@ -121,6 +142,7 @@ void loop() { open_redirect(&err); open_redirect(&out); + open_redirect(&in); if (is_builtin(args->array[0])) { run_builtin(args); @@ -129,6 +151,7 @@ void loop() { launch_program(args); } + close_redirect(&in); close_redirect(&out); close_redirect(&err); diff --git a/src/redirect.c b/src/redirect.c index 2cb8376..6d950ef 100644 --- a/src/redirect.c +++ b/src/redirect.c @@ -27,12 +27,7 @@ void open_redirect(Redirect *redirect) { perror("dup"); } else { - if (redirect->append) { - redirect->fd_new = open(redirect->filename, O_WRONLY | O_CREAT | O_APPEND, 0664); - } - else { - redirect->fd_new = open(redirect->filename, O_WRONLY | O_CREAT | O_TRUNC, 0664); - } + redirect->fd_new = open(redirect->filename, redirect->flags, 0664); if (redirect->fd_new == -1) { fprintf(stderr, "open: Could not open file %s: \"%s\"\n", redirect->filename, strerror(errno)); free(redirect->filename);