diff options
Diffstat (limited to 'lib')
-rw-r--r-- | lib/functions.c | 270 | ||||
-rw-r--r-- | lib/getmountlist.c | 45 | ||||
-rw-r--r-- | lib/lib.h | 51 |
3 files changed, 366 insertions, 0 deletions
diff --git a/lib/functions.c b/lib/functions.c new file mode 100644 index 00000000..44f21b55 --- /dev/null +++ b/lib/functions.c @@ -0,0 +1,270 @@ +/* vi: set sw=4 ts=4 :*/ +/* functions.c - reusable stuff. + * + * Functions with the x prefix are wrappers for library functions. They either + * succeed or kill the program with an error message, but never return failure. + * They usually have the same arguments and return value as the function they + * wrap. + * + * Copyright 2006 Rob Landley <rob@landley.net> + */ + +#include "toys.h" + +void verror_msg(char *msg, int err, va_list va) +{ + fprintf(stderr, "%s: ", toys.which->name); + vfprintf(stderr, msg, va); + if (err) fprintf(stderr, ": %s", strerror(err)); + putc('\n', stderr); +} + +void error_msg(char *msg, ...) +{ + va_list va; + + va_start(va, msg); + verror_msg(msg, 0, va); + va_end(va); +} + +void perror_msg(char *msg, ...) +{ + va_list va; + + va_start(va, msg); + verror_msg(msg, errno, va); + va_end(va); +} + +// Die with an error message. +void error_exit(char *msg, ...) +{ + va_list va; + + va_start(va, msg); + verror_msg(msg, 0, va); + va_end(va); + + exit(toys.exitval); +} + +// Die with an error message and strerror(errno) +void perror_exit(char *msg, ...) +{ + va_list va; + + va_start(va, msg); + verror_msg(msg, errno, va); + va_end(va); + + exit(toys.exitval); +} + +// Like strncpy but always null terminated. +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"); + + return ret; +} + +// Die unless we can allocate prezeroed memory. +void *xzalloc(size_t size) +{ + void *ret = xmalloc(size); + bzero(ret,size); + return ret; +} + +// 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) +{ + *ptr = realloc(*ptr, size); + if (!*ptr) error_exit("xrealloc"); +} + +// Die unless we can allocate a copy of this string. +void *xstrndup(char *s, size_t n) +{ + void *ret = xmalloc(++n); + strlcpy(ret, s, n); + + return ret; +} + +// Die unless we can allocate enough space to sprintf() into. +char *xmsprintf(char *format, ...) +{ + va_list va; + int len; + char *ret; + + // How long is it? + + va_start(va, format); + len = vsnprintf(0, 0, format, va); + len++; + va_end(va); + + // Allocate and do the sprintf() + ret = xmalloc(len); + va_start(va, format); + vsnprintf(ret, len, format, va); + va_end(va); + + return ret; +} + +// Die unless we can exec argv[] (or run builtin command). Note that anything +// with a path isn't a builtin, so /bin/sh won't match the builtin sh. +void xexec(char **argv) +{ + toy_exec(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; +} + +// Read from file handle, retrying if interrupted. +ssize_t reread(int fd, void *buf, size_t count) +{ + ssize_t len; + for (;;) { + len = read(fd, buf, count); + if (len >= 0 || errno != EINTR) return len; + } +} + +// Keep reading until full or EOF +ssize_t readall(int fd, void *buf, size_t count) +{ + size_t len = 0; + while (len<count) { + int i = reread(fd, buf, count); + if (!i) return len; + if (i<0) return i; + count += i; + } + + return count; +} + +// Die if we can't fill a buffer +void xread(int fd, char *buf, size_t count) +{ + if (count != readall(fd, buf, count)) perror_exit("xread"); +} + +char *xgetcwd(void) +{ + char *buf = getcwd(NULL, 0); + if (!buf) error_exit("xgetcwd"); + + return buf; +} + +// Find this file in a colon-separated path. + +char *find_in_path(char *path, char *filename) +{ + char *next, *res = NULL, *cwd = xgetcwd(); + + while ((next = index(path,':'))) { + int len = next-path; + + if (len==1) res = xmsprintf("%s/%s", cwd, filename); + else res = xmsprintf("%*s/%s",len-1,path,filename); + // Is there a file here we can execute? + if (!access(res, X_OK)) { + struct stat st; + // Confirm it's not a directory. + if (!stat(res, &st) && S_ISREG(st.st_mode)) break; + } + free(res); + res = NULL; + } + free(cwd); + + return res; +} + +// Convert unsigned int to ascii, writing into supplied buffer. A truncated +// result contains the first few digits of the result ala strncpy, and is +// always null terminated (unless buflen is 0). +void utoa_to_buf(unsigned n, char *buf, unsigned buflen) +{ + int i, out = 0; + + if (buflen) { + for (i=1000000000; i; i/=10) { + int res = n/i; + + if ((res || out || i == 1) && --buflen>0) { + out++; + n -= res*i; + *buf++ = '0' + res; + } + } + *buf = 0; + } +} + +// Convert signed integer to ascii, using utoa_to_buf() +void itoa_to_buf(int n, char *buf, unsigned buflen) +{ + if (buflen && n<0) { + n = -n; + *buf++ = '-'; + buflen--; + } + utoa_to_buf((unsigned)n, buf, buflen); +} + +// This static buffer is used by both utoa() and itoa(), calling either one a +// second time will overwrite the previous results. +// +// The longest 32 bit integer is -2 billion plus a null terminator: 12 bytes. +// Note that int is always 32 bits on any remotely unix-like system, see +// http://www.unix.org/whitepapers/64bit.html for details. + +static char itoa_buf[12]; + +// Convert unsigned integer to ascii, returning a static buffer. +char *utoa(unsigned n) +{ + utoa_to_buf(n, itoa_buf, sizeof(itoa_buf)); + + return itoa_buf; +} + +char *itoa(int n) +{ + itoa_to_buf(n, itoa_buf, sizeof(itoa_buf)); + + return itoa_buf; +} diff --git a/lib/getmountlist.c b/lib/getmountlist.c new file mode 100644 index 00000000..8410a923 --- /dev/null +++ b/lib/getmountlist.c @@ -0,0 +1,45 @@ +/* vi: set sw=4 ts=4 : */ +/* getmountlist.c - Get a linked list of mount points, with stat information. + * + * Copyright 2006 Rob Landley <rob@landley.net> + */ + +#include "toys.h" + +#include <mntent.h> + +char *path_mounts = "/proc/mounts"; + +// Get a list of mount points from /etc/mtab or /proc/mounts, including +// statvfs() information. This returns a reversed list, which is good for +// finding overmounts and such. + +struct mtab_list *getmountlist(int die) +{ + FILE *fp; + struct mtab_list *mtlist, *mt; + struct mntent me; + char evilbuf[2*PATH_MAX]; + + mtlist = 0; + if (!(fp = setmntent(path_mounts, "r"))) { + if (die) error_exit("cannot open %s", path_mounts); + } else { + while (getmntent_r(fp, &me, evilbuf, sizeof(evilbuf))) { + mt = xzalloc(sizeof(struct mtab_list) + strlen(me.mnt_fsname) + + strlen(me.mnt_dir) + strlen(me.mnt_type) + 3); + mt->next = mtlist; + // Get information about this filesystem. Yes, we need both. + stat(me.mnt_dir, &(mt->stat)); + statvfs(me.mnt_dir, &(mt->statvfs)); + // Remember information from /proc/mounts + strcpy(mt->type, me.mnt_type); + mt->dir = mt->type + strlen(mt->type) + 1; + strcpy(mt->dir, me.mnt_dir); + mt->device = mt->dir + strlen(mt->dir) + 1; + strcpy(mt->device, me.mnt_fsname); + mtlist = mt; + } + } + return mtlist; +} diff --git a/lib/lib.h b/lib/lib.h new file mode 100644 index 00000000..28888a49 --- /dev/null +++ b/lib/lib.h @@ -0,0 +1,51 @@ +/* vi: set ts=4 :*/ +/* lib.h - header file for lib directory + * + * Copyright 2006 Rob Landley <rob@landley.net> + */ + +// functions.c +void verror_msg(char *msg, int err, va_list va); +void error_msg(char *msg, ...); +void perror_msg(char *msg, ...); +void error_exit(char *msg, ...); +void perror_exit(char *msg, ...); +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 *xstrndup(char *s, size_t n); +char *xmsprintf(char *format, ...); +void xexec(char **argv); +int xopen(char *path, int flags, int mode); +FILE *xfopen(char *path, char *mode); +ssize_t reread(int fd, void *buf, size_t count); +ssize_t readall(int fd, void *buf, size_t count); +void xread(int fd, char *buf, size_t count); +char *xgetcwd(void); +char *find_in_path(char *path, char *filename); +void utoa_to_buf(unsigned n, char *buf, unsigned buflen); +void itoa_to_buf(int n, char *buf, unsigned buflen); +char *utoa(unsigned n); +char *itoa(int n); + +// llist.c +void llist_free(void *list, void (*freeit)(void *data)); + +struct string_list { + struct string_list *next; + char *str; +}; + +// getmountlist.c +struct mtab_list { + struct mtab_list *next; + struct stat stat; + struct statvfs statvfs; + char *dir; + char *device; + char type[0]; +}; + +struct mtab_list *getmountlist(int die); + |