From 4f344e356d2c36c4b1df46917eaef25f82ca79a9 Mon Sep 17 00:00:00 2001 From: landley Date: Thu, 5 Oct 2006 16:18:03 -0400 Subject: Infrastructure, first drop of toy shell, and a bit of work on df. --- lib/functions.c | 65 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 lib/functions.c (limited to 'lib/functions.c') diff --git a/lib/functions.c b/lib/functions.c new file mode 100644 index 00000000..3d9a8aca --- /dev/null +++ b/lib/functions.c @@ -0,0 +1,65 @@ +/* vi: set ts=4 :*/ +/* functions.c - reusable stuff. + * + * Functions with the x prefix never return failure, they either succeed or + * kill the program with an error message. + */ + +#include "toys.h" + +// Die with an error message. +void error_exit(char *msg, ...) +{ + va_list args; + + va_start(args, msg); + fprintf(stderr, "%s: ", toys.which->name); + vfprintf(stderr, msg, args); + va_end(args); + exit(toys.exitval); +} + +void strlcpy(char *dest, char *src, size_t size) +{ + strncpy(dest,src,size); + dest[size-1] = 0; +} + +// Die unless we can allocate memory. +void *xmalloc(size_t size) +{ + void *ret = malloc(size); + if (!ret) error_exit("xmalloc"); +} + +// Die unless we can copy this string. +void *xstrndup(char *s, size_t n) +{ + void *ret = xmalloc(++n); + strlcpy(ret, s, n); + + return ret; +} + +// Die unless we can exec argv[] +void *xexec(char **argv) +{ + execvp(argv[0], argv); + error_exit("No %s", argv[0]); +} + +// Die unless we can open/create a file, returning file descriptor. +int xopen(char *path, int flags, int mode) +{ + int fd = open(path, flags, mode); + if (fd == -1) error_exit("No file %s\n", path); + return fd; +} + +// Die unless we can open/create a file, returning FILE *. +FILE *xfopen(char *path, char *mode) +{ + FILE *f = fopen(path, mode); + if (!f) error_exit("No file %s\n", path); + return f; +} -- cgit v1.2.3