diff options
| -rw-r--r-- | lib/lib.c | 32 | ||||
| -rw-r--r-- | lib/lib.h | 3 | ||||
| -rw-r--r-- | toys/Config.in | 16 | ||||
| -rw-r--r-- | toys/toylist.h | 1 | ||||
| -rw-r--r-- | toys/toysh.c | 2 |
5 files changed, 49 insertions, 5 deletions
@@ -94,10 +94,12 @@ void *xzalloc(size_t size) // Die unless we can change the size of an existing allocation, possibly // moving it. (Notice different arguments from libc function.) -void xrealloc(void **ptr, size_t size) +void *xrealloc(void *ptr, size_t size) { - *ptr = realloc(*ptr, size); - if (!*ptr) error_exit("xrealloc"); + ptr = realloc(ptr, size); + if (!ptr) error_exit("xrealloc"); + + return ptr; } // Die unless we can allocate a copy of this many bytes of string. @@ -452,6 +454,30 @@ off_t fdlength(int fd) return pos + 1; } +// This can return null (meaning file not found). It just won't return null +// for memory allocation reasons. +char *xreadlink(char *name) +{ + int len, size = 0; + char *buf = 0; + + // Grow by 64 byte chunks until it's big enough. + for(;;) { + size +=64; + buf = xrealloc(buf, size); + len = readlink(name, buf, size); + + if (len<0) { + free(buf); + return 0; + } + if (len<size) { + buf[len]=0; + return buf; + } + } +} + /* This might be of use or might not. Unknown yet... @@ -40,7 +40,7 @@ void usage_exit(void); void strlcpy(char *dest, char *src, size_t size); void *xmalloc(size_t size); void *xzalloc(size_t size); -void xrealloc(void **ptr, size_t size); +void *xrealloc(void *ptr, size_t size); void *xstrndup(char *s, size_t n); void *xstrdup(char *s); char *xmsprintf(char *format, ...); @@ -67,6 +67,7 @@ char *utoa(unsigned n); char *itoa(int n); long atolx(char *c); off_t fdlength(int fd); +char *xreadlink(char *name); struct dirtree *read_dirtree_node(char *path); struct dirtree *read_dirtree(char *path, struct dirtree *parent); diff --git a/toys/Config.in b/toys/Config.in index 5634436c..5aae5c54 100644 --- a/toys/Config.in +++ b/toys/Config.in @@ -194,6 +194,22 @@ config PWD The print working directory command prints the current directory. +config READLINK + bool "readlink" + default n + help + usage: readlink + + Show what a symbolic link points to. + +config READLINK_FINAL + bool "readlink -f" + default n + help + usage: readlink [-f] + + -f Show final location, including normal files and multiple symlinks. + config SYNC bool "sync" default n diff --git a/toys/toylist.h b/toys/toylist.h index d686877c..125b0376 100644 --- a/toys/toylist.h +++ b/toys/toylist.h @@ -94,6 +94,7 @@ USE_HELLO(NEWTOY(hello, NULL, TOYFLAG_USR)) USE_MKE2FS(NEWTOY(mke2fs, MKE2FS_OPTSTRING, TOYFLAG_SBIN)) USE_ONEIT(NEWTOY(oneit, "+<1p", TOYFLAG_SBIN)) USE_PWD(NEWTOY(pwd, NULL, TOYFLAG_BIN)) +USE_READLINK(NEWTOY(readlink, "<1f", TOYFLAG_BIN)) USE_TOYSH(OLDTOY(sh, toysh, "c:i", TOYFLAG_BIN)) USE_SYNC(NEWTOY(sync, NULL, TOYFLAG_BIN)) USE_TOUCH(NEWTOY(touch, "l#t:r:mca", TOYFLAG_BIN)) diff --git a/toys/toysh.c b/toys/toysh.c index c383b89a..ef061bde 100644 --- a/toys/toysh.c +++ b/toys/toysh.c @@ -61,7 +61,7 @@ static char *parse_word(char *start, struct command **cmd) // Allocate more space if there's no room for NULL terminator. if (!((*cmd)->argc & 7)) - xrealloc((void **)cmd, + *cmd=xrealloc(*cmd, sizeof(struct command) + ((*cmd)->argc+8)*sizeof(char *)); (*cmd)->argv[(*cmd)->argc] = 0; return end; |