diff options
| -rw-r--r-- | Makefile | 2 | ||||
| -rw-r--r-- | depipe_strings.c | 3 | ||||
| -rw-r--r-- | pipe.c | 40 | ||||
| -rw-r--r-- | strpbrk.c | 57 |
4 files changed, 59 insertions, 43 deletions
@@ -1,4 +1,4 @@ -BINS = ascii class depipe_strings dup fpipe realloc strpbrk strsep tokenizer +BINS = ascii class depipe_strings dup fpipe pipe realloc strpbrk strsep tokenizer CC = gcc DBGFLAGS = -g -O0 ifdef DEBUG diff --git a/depipe_strings.c b/depipe_strings.c index 597ade8..61115d7 100644 --- a/depipe_strings.c +++ b/depipe_strings.c @@ -15,7 +15,7 @@ char **depipe_string(const char *, int *); int main(int argc, char **argv) { int count; - char *line = " ls -1 | wc -l | cut -n1 | less | rtfm| bro "; + char *line = " ls -1 | wc -l | cut -b 6-7"; char **depiped = depipe_string(line, &count); int j; @@ -27,6 +27,7 @@ int main(int argc, char **argv) return 0; } +/* chops and counts strings with arguments that are separated by pipes */ char **depipe_string(const char *line, int *count) { char *last = (char *) line; @@ -0,0 +1,40 @@ +#include <unistd.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#define MAX_LINE 80 +#define PIPE_STDIN 0 +#define PIPE_STDOUT 1 + +int main(int argc, char **argv) +{ + const char *string = {"A sample message."}; + int ret, myPipe[2]; + char buffer[MAX_LINE+1]; + + /* create the pipe */ + ret = pipe(myPipe); + + if (ret == 0) + { + /* write message into the pipe */ + write(myPipe[PIPE_STDOUT], string, strlen(string)); + + /* read the message from the pipe */ + ret = read(myPipe[PIPE_STDIN], buffer, MAX_LINE); + + /* null terminate the string */ + buffer[ret] = 0; + + printf("%s\n", buffer); + } + else + { + perror("pipe"); + exit(EXIT_FAILURE); + } + + return 0; +} + @@ -2,20 +2,27 @@ #include <stdlib.h> #include <string.h> -char **redir_chop(const char *line) +char **redir_chop(const char *, const char); + +/* chops a line into 2 string that are seperated by redir_delim */ +char **redir_chop(const char *line, const char redir_delim) { if (!line) return NULL; - const char *redir_delim = "><"; + const char *delim = &redir_delim; - char *pipe_redir = strpbrk(line, redir_delim); + char *pipe_redir = strpbrk(line, delim); if (pipe_redir == NULL) return NULL; size_t redir_delta = pipe_redir - line; - char *former = (char *) malloc(sizeof(char) * 100); - char *latter = (char *) malloc(sizeof(char) * 100); + char **ret = (char **) malloc(sizeof(char *) * 2); + ret[0] = (char *) malloc(sizeof(char) * 256 * 2); + ret[1] = ret[0] + 256; + + char *former = ret[0]; + char *latter = ret[1]; strncpy(former, line, redir_delta); former[redir_delta] ='\0'; @@ -31,50 +38,18 @@ char **redir_chop(const char *line) ; strncpy(latter, line+j, (line + strlen(line)) - pipe_redir); - char **ret = (char **) malloc(sizeof(char *) * 2); - ret[0] = (char *) former; - ret[1] = (char *) latter; - return ret; } int main(int argc, char *argv[]) { const char *line = "ls -1 -al > filename.txt"; - -#if 0 - const char *redir_delim = "><"; - - char *pipe_redir = strpbrk(line, redir_delim); - size_t redir_delta = pipe_redir - line; - char *former = (char *) malloc(sizeof(char) * 100); - char *latter = (char *) malloc(sizeof(char) * 100); - - strncpy(former, line, redir_delta); - former[redir_delta] ='\0'; - - /* delete spaces at the end of former string */ - int i = strlen(former) - 1; - while (former[i] == ' ') - former[i--] = '\0'; - - /* skip spaces in latter string and then copy over */ - int j = redir_delta; - while (line[++j] == ' ') - ; - strncpy(latter, line+j, (line + strlen(line)) - pipe_redir); - - printf("former string: \"%s\"\n", former); - printf("latter string: \"%s\"\n", latter); - - free(former); - free(latter); -#endif - - char **chopped = redir_chop(line); + char **chopped = redir_chop(line, '>'); printf("former string: \"%s\"\n", chopped[0]); - printf("latter string: \"%s\"\n", chopped[1]); + printf("latter string: \"%s\"\n", chopped[1]); + + free(chopped); return 0; } |