Dear Gerlando Falauto, WD prodded me too long to review this patchset ;-D
> 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. > > Also allow for selectively importing/resetting variables. > > So add 3 new arguments to himport_r(): > o "nvars", "vars":, number and list of variables to take into account > (0 means ALL) > > o "apply" callback function to check whether a variable can be > overwritten, and possibly immediately apply the changes; > when NULL, no check is performed. > > Signed-off-by: Gerlando Falauto <gerlando.fala...@keymile.com> [...] > + } > +#if defined(CONFIG_CMD_NET) > + else if (strcmp(name, "bootfile") == 0) { > + copy_filename(BootFile, newval, sizeof(BootFile)); Can you remove the camel-case here please? > + 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); > @@ -337,34 +412,6 @@ 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(name, "ipaddr") == 0) { > - char *s = argv[2]; /* always use only one arg */ > - char *e; > - unsigned long addr; > - bd->bi_ip_addr = 0; > - for (addr = 0, i = 0; i < 4; ++i) { > - ulong val = s ? simple_strtoul(s, &e, 10) : 0; > - addr <<= 8; > - addr |= val & 0xFF; > - if (s) > - s = *e ? e + 1 : e; > - } > - bd->bi_ip_addr = htonl(addr); > - return 0; > - } else 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; > } > > @@ -886,7 +933,8 @@ static int do_env_import(cmd_tbl_t *cmdtp, int flag, > addr = (char *)ep->data; > } > > - if (himport_r(&env_htab, addr, size, sep, del ? 0 : H_NOCLEAR) == 0) { > + if (himport_r(&env_htab, addr, size, sep, del ? 0 : H_NOCLEAR, > + 0, NULL, NULL) == 0) { > error("Environment import failed: errno = %d\n", errno); > return 1; > } > diff --git a/common/env_common.c b/common/env_common.c > index 8a71096..7e2bb2f 100644 > --- a/common/env_common.c > +++ b/common/env_common.c > @@ -175,7 +175,8 @@ void set_default_env(const char *s) > } > > if (himport_r(&env_htab, (char *)default_environment, > - sizeof(default_environment), '\0', 0) == 0) > + sizeof(default_environment), '\0', 0, > + 0, NULL, NULL) == 0) > error("Environment import failed: errno = %d\n", errno); > > gd->flags |= GD_FLG_ENV_READY; > @@ -200,7 +201,8 @@ int env_import(const char *buf, int check) > } > } > > - if (himport_r(&env_htab, (char *)ep->data, ENV_SIZE, '\0', 0)) { > + if (himport_r(&env_htab, (char *)ep->data, ENV_SIZE, '\0', 0, > + 0, NULL, NULL)) { > gd->flags |= GD_FLG_ENV_READY; > return 1; > } > diff --git a/include/environment.h b/include/environment.h > index 3c145af..3a3e6b8 100644 > --- a/include/environment.h > +++ b/include/environment.h > @@ -193,6 +193,13 @@ void set_default_env(const char *s); > /* Import from binary representation into hash table */ > int env_import(const char *buf, int check); > > +/* > + * Check if variable "name" can be changed from oldval to newval, > + * and if so, apply the changes (e.g. baudrate) > + */ > +int env_check_apply(const char *name, const char *oldval, > + const char *newval, int flag); > + > #endif /* DO_DEPS_ONLY */ > > #endif /* _ENVIRONMENT_H_ */ > diff --git a/include/search.h b/include/search.h > index ef53edb..2a59e03 100644 > --- a/include/search.h > +++ b/include/search.h > @@ -47,6 +47,13 @@ typedef struct entry { > struct _ENTRY; > > /* > + * Callback function to be called for checking whether the given change > may + * be applied or not. Must return 0 for approval, 1 for denial. > + */ > +typedef int (*apply_cb)(const char *name, const char *oldval, > + const char *newval, int flag); Is the typedef really necessary ? > + > +/* > * Family of hash table handling functions. The functions also > * have reentrant counterparts ending with _r. The non-reentrant > * functions all work on a signle internal hashing table. > @@ -94,11 +101,19 @@ extern ssize_t hexport_r(struct hsearch_data *__htab, > const char __sep, char **__resp, size_t __size, > int argc, char * const argv[]); > > +/* > + * nvars, vars: variables to import (nvars == 0 means all) > + * apply_cb: callback function to check validity of the new argument, > + * and possibly apply changes (NULL means accept everything) > + */ > extern int himport_r(struct hsearch_data *__htab, > const char *__env, size_t __size, const char __sep, > - int __flag); > + int __flag, > + int nvars, char * const vars[], > + apply_cb apply); > > /* Flags for himport_r() */ > #define H_NOCLEAR 1 /* do not clear hash table before importing */ > +#define H_FORCE 2 /* overwrite read-only/write-once variables */ Make this 1 << x please. > > #endif /* search.h */ > diff --git a/lib/hashtable.c b/lib/hashtable.c > index abd61c8..75b9b07 100644 > --- a/lib/hashtable.c > +++ b/lib/hashtable.c > @@ -603,6 +603,22 @@ ssize_t hexport_r(struct hsearch_data *htab, const > char sep, * himport() > */ > > +/* Check whether variable name is amongst vars[] */ > +static int process_var(const char *name, int nvars, char * const vars[]) You mean check_var()? > +{ > + int i = 0; > + /* No variables specified means process all of them */ > + if (nvars == 0) > + return 1; > + > + for (i = 0; i < nvars; i++) { > + if (!strcmp(name, vars[i])) > + return 1; > + } > + debug("Skipping non-listed variable %s\n", name); > + return 0; > +} > + > /* > * Import linearized data into hash table. > * > @@ -639,7 +655,9 @@ ssize_t hexport_r(struct hsearch_data *htab, const char > sep, */ > > int himport_r(struct hsearch_data *htab, > - const char *env, size_t size, const char sep, int flag) > + const char *env, size_t size, const char sep, int flag, > + int nvars, char * const vars[], > + apply_cb apply) > { > char *data, *sp, *dp, *name, *value; > > @@ -726,6 +744,8 @@ int himport_r(struct hsearch_data *htab, > *dp++ = '\0'; /* terminate name */ > > debug("DELETE CANDIDATE: \"%s\"\n", name); > + if (!process_var(name, nvars, vars)) > + continue; > > if (hdelete_r(name, htab) == 0) > debug("DELETE ERROR ##############################\n"); > @@ -743,10 +763,31 @@ int himport_r(struct hsearch_data *htab, > *sp++ = '\0'; /* terminate value */ > ++dp; > > + /* Skip variables which are not supposed to be treated */ > + if (!process_var(name, nvars, vars)) > + continue; > + > /* enter into hash table */ > e.key = name; > e.data = value; Do you need to do this if you eventually later figure out you have no apply() callback and you did this for no reason? > > + /* if there is an apply function, check what it has to say */ > + if (apply != NULL) { > + debug("searching before calling cb function" > + " for %s\n", name); > + /* > + * Search for variable in existing env, so to pass > + * its previous value to the apply callback > + */ > + hsearch_r(e, FIND, &rv, htab); > + debug("previous value was %s\n", rv ? rv->data : ""); > + if (apply(name, rv ? rv->data : NULL, value, flag)) { > + debug("callback function refused to set" > + " variable %s, skipping it!\n", name); > + continue; > + } > + } > + > hsearch_r(e, ENTER, &rv, htab); > if (rv == NULL) { > printf("himport_r: can't insert \"%s=%s\" into hash table\n", _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot