diff options
Diffstat (limited to 'lib/backup-files.c')
| -rw-r--r-- | lib/backup-files.c | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/lib/backup-files.c b/lib/backup-files.c new file mode 100644 index 0000000..b9f1b21 --- /dev/null +++ b/lib/backup-files.c @@ -0,0 +1,212 @@ +/* backup-files.c + Andreas Gruenbacher, 18 January 2003 + + `patch -b' fails to back up files correctly if a file occurs + more than once in a patch, so we use this utility instead. +*/ + +/* + - catch SIGINT + - remove backup files and directories +*/ + +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <unistd.h> +#include <stdio.h> +#include <errno.h> +#include <string.h> + +const char *progname; + +void +usage(void) +{ + printf("Usage: %s [-B prefix] [-z suffix] [-f filelist] [-s] [-r|-x]\n" + "\n" + "\tCreate hard linked backup copies of a list of files\n" + "\tread from standard input.\n" + "\n" + "\t-r\tRestore the backup\n" + "\t-x\tRemove backup files and empty parent directories\n" + "\t-B\tPath name prefix for backup files\n" + "\t-z\tPath name suffix for backup files\n" + "\t-s\tSilent operation; only print error messages\n\n", + progname); +} + +void +create_parents(char *filename) +{ + struct stat st; + char *f = strchr(filename, '/'); + + if (f == NULL) + return; + *f = '\0'; + if (stat(f, &st) != 0) { + while (f != NULL) { + *f = '\0'; + mkdir(filename, 0777); + *f = '/'; + f = strchr(f+1, '/'); + } + } else { + *f = '/'; + } +} + +void +remove_parents(char *filename) +{ + char *f; + + while ((f = strrchr(filename, '/')) != NULL) { + *f = '\0'; + rmdir(filename); + } +} + +enum { what_backup, what_restore, what_remove }; + +#define LINE_LENGTH 1024 + +int +main(int argc, char *argv[]) +{ + char orig[LINE_LENGTH], *o, backup[LINE_LENGTH]; + FILE *file; + + const char *opt_prefix="", *opt_suffix="", *opt_file=NULL; + int opt_silent=0, opt_what=what_backup; + int opt, status=0; + + progname = argv[0]; + + while ((opt = getopt(argc, argv, "rxB:z:f:sh")) != -1) { + switch(opt) { + case 'r': + opt_what = what_restore; + break; + + case 'x': + opt_what = what_remove; + break; + + case 'B': + opt_prefix = optarg; + break; + + case 'f': + opt_file = optarg; + break; + + case 'z': + opt_suffix = optarg; + break; + + case 's': + opt_silent = 1; + break; + + case 'h': + default: + usage(); + return 0; + } + } + + if ((*opt_prefix == '\0' && *opt_suffix == '\0') || optind != argc) { + usage(); + return 1; + } + + if (opt_file != NULL) { + if ((file = fopen(opt_file, "r")) == NULL) { + perror(opt_file); + return 1; + } + } else { + file = stdin; + } + + while (fgets(orig, sizeof(orig), file)) { + if (strlen(opt_prefix) + strlen(orig) + strlen(opt_suffix) >= + sizeof(backup)) { + perror("Line buffer too small\n"); + return 1; + } + + o = strchr(orig, '\0'); + if (o > orig && *(o-1) == '\n') + *(o-1) = '\0'; + if (*orig == '\0') + continue; + + snprintf(backup, sizeof(backup), "%s%s%s", + opt_prefix, orig, opt_suffix); + + if (opt_what == what_backup) { + int fd; + create_parents(backup); + + if (link(orig, backup) == 0) { + if (!opt_silent) + printf("Copying %s\n", orig); + } else if ((fd = creat(backup, 0666)) != -1) { + close(fd); + if (!opt_silent) + printf("New file %s\n", orig); + } else { + perror(backup); + return 1; + } + } else if (opt_what == what_restore) { + struct stat st; + + create_parents(orig); + + if (stat(backup, &st) != 0) { + perror(backup); + status=1; + continue; + } + if (st.st_size == 0) { + if (unlink(orig) == 0 || errno == ENOENT) { + if (!opt_silent) + printf("Removing %s\n", orig); + unlink(backup); + remove_parents(backup); + } else { + if (errno != ENOENT) { + perror(orig); + status=1; + } + } + } else { + unlink(orig); + if (link(backup, orig) == 0) { + if (!opt_silent) + printf("Restoring %s\n", orig); + unlink(backup); + remove_parents(backup); + } else { + fprintf(stderr, "Could not restore " + "file `%s' to `%s': %s\n", + backup, orig, strerror(errno)); + status=1; + } + } + } else { + unlink(backup); + remove_parents(backup); + } + } + + if (file != stdin) { + fclose(file); + } + + return status; +} |