The logic of checking special parameters (e.g. baudrate, stdin, stdout, for a valid value and/or whether can be overwritten) and applying the new value to the running system is now all within a single function env_check_apply() which can be called whenever changes are made to the environment, no matter if by set, default or import.
With this patch env_check_apply() is only called by "env set", retaining previous behavior.
Signed-off-by: Gerlando Falauto gerlando.falauto@keymile.com --- common/cmd_nvedit.c | 141 +++++++++++++++++++++++++++++++++------------------ include/search.h | 3 +- 2 files changed, 94 insertions(+), 50 deletions(-)
diff --git a/common/cmd_nvedit.c b/common/cmd_nvedit.c index b8c7676..2f5dcbc 100644 --- a/common/cmd_nvedit.c +++ b/common/cmd_nvedit.c @@ -198,31 +198,19 @@ static int do_env_grep(cmd_tbl_t *cmdtp, int flag, #endif
/* - * Set a new environment variable, - * or replace or delete an existing one. + * Perform consistency checking before setting, replacing, or deleting an + * environment variable, then (if successful) apply the changes to internals so + * to make them effective. Code for this function was taken out of + * _do_env_set(), which now calls it instead. + * Returns 0 in case of success, 1 in case of failure. + * When (flag & H_FORCE) is set, do not print out any error message and force + * overwriting of write-once variables. */ -int _do_env_set(int flag, int argc, char * const argv[]) + +int env_check_apply(const char *name, const char *oldval, + const char *newval, int flag) { - int i, len; int console = -1; - char *name, *value, *s; - ENTRY e, *ep; - - name = argv[1]; - - if (strchr(name, '=')) { - printf("## Error: illegal character '=' in variable name" - ""%s"\n", name); - return 1; - } - - env_id++; - /* - * search if variable with this name already exists - */ - e.key = name; - e.data = NULL; - hsearch_r(e, FIND, &ep, &env_htab);
/* Check for console redirection */ if (strcmp(name, "stdin") == 0) @@ -233,59 +221,75 @@ int _do_env_set(int flag, int argc, char * const argv[]) console = stderr;
if (console != -1) { - if (argc < 3) { /* Cannot delete it! */ - printf("Can't delete "%s"\n", name); + if ((newval == NULL) || (*newval == '\0')) { + /* We cannot delete stdin/stdout/stderr */ + if ((flag & H_FORCE) == 0) + printf("Can't delete "%s"\n", name); return 1; }
#ifdef CONFIG_CONSOLE_MUX - if (iomux_doenv(console, argv[2])) + if (iomux_doenv(console, newval)) return 1; #else /* Try assigning specified device */ - if (console_assign(console, argv[2]) < 0) + if (console_assign(console, newval) < 0) return 1;
#ifdef CONFIG_SERIAL_MULTI - if (serial_assign(argv[2]) < 0) + if (serial_assign(newval) < 0) return 1; #endif #endif /* CONFIG_CONSOLE_MUX */ }
/* - * Some variables like "ethaddr" and "serial#" can be set only - * once and cannot be deleted; also, "ver" is readonly. + * Some variables like "ethaddr" and "serial#" can be set only once and + * cannot be deleted, unless CONFIG_ENV_OVERWRITE is defined. */ - if (ep) { /* variable exists */ #ifndef CONFIG_ENV_OVERWRITE + if (oldval != NULL && /* variable exists */ + (flag & H_FORCE) == 0) { /* and we are not forced */ if (strcmp(name, "serial#") == 0 || (strcmp(name, "ethaddr") == 0 #if defined(CONFIG_OVERWRITE_ETHADDR_ONCE) && defined(CONFIG_ETHADDR) - && strcmp(ep->data, MK_STR(CONFIG_ETHADDR)) != 0 + && strcmp(oldval, MK_STR(CONFIG_ETHADDR)) != 0 #endif /* CONFIG_OVERWRITE_ETHADDR_ONCE && CONFIG_ETHADDR */ )) { printf("Can't overwrite "%s"\n", name); return 1; } + } #endif + /* + * When we change baudrate, or we are doing an env default -a + * (which will erase all variables prior to calling this), + * we want the baudrate to actually change - for real. + */ + if (oldval != NULL || /* variable exists */ + (flag & H_NOCLEAR) == 0) { /* or env is clear */ /* * Switch to new baudrate if new baudrate is supported */ if (strcmp(name, "baudrate") == 0) { - int baudrate = simple_strtoul(argv[2], NULL, 10); + int baudrate = simple_strtoul(newval, NULL, 10); int i; for (i = 0; i < N_BAUDRATES; ++i) { if (baudrate == baudrate_table[i]) break; } if (i == N_BAUDRATES) { - printf("## Baudrate %d bps not supported\n", - baudrate); + if ((flag & H_FORCE) == 0) + printf("## Baudrate %d bps not " + "supported\n", baudrate); return 1; } + if (gd->baudrate == baudrate) { + /* If unchanged, we just say it's OK */ + return 0; + } printf("## Switch baudrate to %d bps and" - "press ENTER ...\n", baudrate); + "press ENTER ...\n", baudrate); udelay(50000); gd->baudrate = baudrate; #if defined(CONFIG_PPC) || defined(CONFIG_MCF52x2) @@ -299,6 +303,59 @@ int _do_env_set(int flag, int argc, char * const argv[]) } }
+ /* + * Some variables should be updated when the corresponding + * entry in the environment is changed + */ + if (strcmp(name, "loadaddr") == 0) { + load_addr = simple_strtoul(newval, NULL, 16); + return 0; + } +#if defined(CONFIG_CMD_NET) + else if (strcmp(name, "bootfile") == 0) { + copy_filename(BootFile, newval, sizeof(BootFile)); + return 0; + } +#endif + return 0; +} + +/* + * Set a new environment variable, + * or replace or delete an existing one. +*/ +int _do_env_set(int flag, int argc, char * const argv[]) +{ + int i, len; + char *name, *value, *s; + ENTRY e, *ep; + + name = argv[1]; + value = argv[2]; + + if (strchr(name, '=')) { + printf("## Error: illegal character '='" + "in variable name "%s"\n", name); + return 1; + } + + env_id++; + /* + * search if variable with this name already exists + */ + e.key = name; + e.data = NULL; + hsearch_r(e, FIND, &ep, &env_htab); + + /* + * Perform requested checks. Notice how since we are overwriting + * a single variable, we need to set H_NOCLEAR + */ + if (env_check_apply(name, ep ? ep->data : NULL, value, H_NOCLEAR)) { + debug("check function did not approve, refusing\n"); + return 1; + } + /* Delete only ? */ if (argc < 3 || argv[2] == NULL) { int rc = hdelete_r(name, &env_htab); @@ -336,20 +393,6 @@ int _do_env_set(int flag, int argc, char * const argv[]) return 1; }
- /* - * Some variables should be updated when the corresponding - * entry in the environment is changed - */ - if (strcmp(argv[1], "loadaddr") == 0) { - load_addr = simple_strtoul(argv[2], NULL, 16); - return 0; - } -#if defined(CONFIG_CMD_NET) - else if (strcmp(argv[1], "bootfile") == 0) { - copy_filename(BootFile, argv[2], sizeof(BootFile)); - return 0; - } -#endif return 0; }
diff --git a/include/search.h b/include/search.h index ef53edb..a4a5ef4 100644 --- a/include/search.h +++ b/include/search.h @@ -99,6 +99,7 @@ extern int himport_r(struct hsearch_data *__htab, int __flag);
/* Flags for himport_r() */ -#define H_NOCLEAR 1 /* do not clear hash table before importing */ +#define H_NOCLEAR (1 << 0) /* do not clear hash table before importing */ +#define H_FORCE (1 << 1) /* overwrite read-only/write-once variables */
#endif /* search.h */