sfdisk: require confirmation before write to the device

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/disk-utils/sfdisk.c b/disk-utils/sfdisk.c
index 61d57cbe6bcc7f236197c8d3048cbc61ee5e1a80..3357ed2aaeb54b3eaeb4c2e15eed1516a3f61c40 100644 (file)
--- a/disk-utils/sfdisk.c
+++ b/disk-utils/sfdisk.c
@@ -52,6 +52,7 @@ UL_DEBUG_DEFINE_MASKANEMS(sfdisk) = UL_DEBUG_EMPTY_MASKNAMES;
 #define SFDISKPROG_DEBUG_INIT  (1 << 1)
 #define SFDISKPROG_DEBUG_PARSE (1 << 2)
 #define SFDISKPROG_DEBUG_MISC  (1 << 3)
+#define SFDISKPROG_DEBUG_ASK   (1 << 4)
 #define SFDISKPROG_DEBUG_ALL   0xFFFF
 
 #define DBG(m, x)       __UL_DBG(sfdisk, SFDISKPROG_DEBUG_, m, x)
@@ -83,9 +84,35 @@ static void sfdiskprog_init_debug(void)
        __UL_INIT_DEBUG(sfdisk, SFDISKPROG_DEBUG_, 0, SFDISK_DEBUG);
 }
 
+
+static int get_user_reply(const char *prompt, char *buf, size_t bufsz)
+{
+       char *p;
+       size_t sz;
+
+       fputs(prompt, stdout);
+       fflush(stdout);
+
+       if (!fgets(buf, bufsz, stdin))
+               return 1;
+
+       for (p = buf; *p && !isgraph(*p); p++); /* get first non-blank */
+
+       if (p > buf)
+               memmove(buf, p, p - buf);       /* remove blank space */
+       sz = strlen(buf);
+       if (sz && *(buf + sz - 1) == '\n')
+               *(buf + sz - 1) = '\0';
+
+       DBG(ASK, ul_debug("user's reply: >>>%s<<<", buf));
+       return 0;
+}
+
 static int ask_callback(struct fdisk_context *cxt, struct fdisk_ask *ask,
                    void *data __attribute__((__unused__)))
 {
+       int rc = 0;
+
        assert(cxt);
        assert(ask);
 
@@ -107,10 +134,29 @@ static int ask_callback(struct fdisk_context *cxt, struct fdisk_ask *ask,
                fprintf(stderr, ": %m\n");
                color_fdisable(stderr);
                break;
+       case FDISK_ASKTYPE_YESNO:
+       {
+               char buf[BUFSIZ];
+               fputc('\n', stdout);
+               do {
+                       int x;
+                       fputs(fdisk_ask_get_query(ask), stdout);
+                       rc = get_user_reply(_(" [Y]es/[N]o: "), buf, sizeof(buf));
+                       if (rc)
+                               break;
+                       x = rpmatch(buf);
+                       if (x == 1 || x == 0) {
+                               fdisk_ask_yesno_set_result(ask, x);
+                               break;
+                       }
+               } while(1);
+               DBG(ASK, ul_debug("yes-no ask: reply '%s' [rc=%d]", buf, rc));
+               break;
+       }
        default:
                break;
        }
-       return 0;
+       return rc;
 }
 
 static void sfdisk_init(struct sfdisk *sf)
@@ -351,8 +397,9 @@ static void command_fdisk_help(void)
        color_scheme_enable("help-title", UL_COLOR_BOLD);
        fputs(_(" Commands:\n"), stdout);
        color_disable();
-       fputs(_("   write    interupts input and write the partition table.\n"), stdout);
-       fputs(_("   abort    interupts input and exit.\n"), stdout);
+       fputs(_("   write    write table to disk and exit\n"), stdout);
+       fputs(_("   quit     show new situation and wait for user's feedbadk before write\n"), stdout);
+       fputs(_("   abort    exit sfdisk shell\n"), stdout);
        fputs(_("   print    print partition table.\n"), stdout);
        fputs(_("   help     this help.\n"), stdout);
 
@@ -387,6 +434,44 @@ static void command_fdisk_help(void)
        fputc('\n', stdout);
 }
 
+enum {
+       SFDISK_DONE_NONE = 0,
+       SFDISK_DONE_EOF,
+       SFDISK_DONE_ABORT,
+       SFDISK_DONE_WRITE,
+       SFDISK_DONE_ASK
+};
+
+/* returns: 0 on success, <0 on error, 1 successfully stop sfdisk */
+static int loop_control_commands(struct sfdisk *sf,
+                                struct fdisk_script *dp,
+                                char *buf)
+{
+       const char *p = skip_blank(buf);
+       int rc = SFDISK_DONE_NONE;
+
+       if (strcmp(p, "print") == 0)
+               list_disklabel(sf->cxt);
+       else if (strcmp(p, "help") == 0)
+               command_fdisk_help();
+       else if (strcmp(p, "quit") == 0)
+               rc = SFDISK_DONE_ASK;
+       else if (strcmp(p, "write") == 0)
+               rc = SFDISK_DONE_WRITE;
+       else if (strcmp(p, "abort") == 0)
+               rc = SFDISK_DONE_ABORT;
+       else {
+               if (isatty(STDIN_FILENO))
+                       fdisk_warnx(sf->cxt, _("unsupported command"));
+               else {
+                       fdisk_warnx(sf->cxt, _("line %d: unsupported command"),
+                                       fdisk_script_get_nlines(dp));
+                       rc = -EINVAL;
+               }
+       }
+       return rc;
+}
+
 
 /*
  * sfdisk <device> [[-N] <partno>]
@@ -471,37 +556,16 @@ static int command_fdisk(struct sfdisk *sf, int argc, char **argv)
                        printf(">>> ");
 
                rc = fdisk_script_read_line(dp, stdin, buf, sizeof(buf));
-
-               if (rc == 1) {          /* end of file */
-                       printf(_("Done.\n"));
-                       rc = 0;
-                       break;
-               } else if (rc < 0) {
-                       const char *p;
-
+               if (rc < 0) {
                        DBG(PARSE, ul_debug("script parsing failed, trying sfdisk specific commands"));
                        buf[sizeof(buf) - 1] = '\0';
-                       p = skip_blank(buf);
-                       rc = 0;
-                       if (strcmp(p, "print") == 0)
-                               list_disklabel(sf->cxt);
-                       else if (strcmp(p, "help") == 0)
-                               command_fdisk_help();
-                       else if (strcmp(p, "write") == 0)
-                               break;
-                       else if (strcmp(p, "abort") == 0) {
-                               rc = -1;
+                       rc = loop_control_commands(sf, dp, buf);
+                       if (rc)
                                break;
-                       } else {
-                               if (isatty(STDIN_FILENO))
-                                       fdisk_warnx(sf->cxt, _("unsupported command"));
-                               else {
-                                       fdisk_warnx(sf->cxt, _("line %d: unsupported command"),
-                                                       fdisk_script_get_nlines(dp));
-                                       break;
-                               }
-                       }
                        continue;
+               } else if (rc == 1) {
+                       rc = SFDISK_DONE_EOF;
+                       break;
                }
 
                nparts = fdisk_table_get_nents(tb);
@@ -532,18 +596,36 @@ static int command_fdisk(struct sfdisk *sf, int argc, char **argv)
                        fdisk_info(sf->cxt, _("Script header accepted."));
        } while (1);
 
-
-       if (!rc) {
+       if (rc != SFDISK_DONE_ABORT) {
                fdisk_info(sf->cxt, _("\nNew situation:"));
                list_disklabel(sf->cxt);
        }
-       if (!rc)
+
+       switch (rc) {
+       case SFDISK_DONE_ASK:
+               if (isatty(STDIN_FILENO)) {
+                       int yes = 0;
+                       fdisk_ask_yesno(sf->cxt, _("Do you want to write this to disk?"), &yes);
+                       if (!yes) {
+                               printf(_("Leaving.\n"));
+                               rc = 0;
+                               break;
+                       }
+               }
+       case SFDISK_DONE_EOF:
+       case SFDISK_DONE_WRITE:
                rc = fdisk_write_disklabel(sf->cxt);
-       if (!rc) {
-               fdisk_info(sf->cxt, _("\nThe partition table has been altered."));
-               fdisk_reread_partition_table(sf->cxt);
-               rc = fdisk_deassign_device(sf->cxt, 0);
+               if (!rc) {
+                       fdisk_info(sf->cxt, _("\nThe partition table has been altered."));
+                       fdisk_reread_partition_table(sf->cxt);
+                       rc = fdisk_deassign_device(sf->cxt, 0);
+               }
+               break;
+       case SFDISK_DONE_ABORT:
+               printf(_("Leaving.\n"));
+               break;
        }
+
        fdisk_unref_script(dp);
        return rc;
 }