From 9ffb7dd9a4688161140a4c19221247566886ef55 Mon Sep 17 00:00:00 2001 From: Eric Andersen Date: Sat, 19 May 2001 03:00:46 +0000 Subject: This is a patch from Vladimir: > I rewrite *local_variable* function in hush.c with: > 1) remove many memory leaks > 2) add support read_only protect (require write builtin function for set this, > I write this special for variable HUSH_VERION=0.01) > 3) commad read set only local variable now > 4) remove many error messages if "set unset export" not defined variable > (bash syntax not put and set error code). Hmm, if I set result to -1, you hush > called waitpid and returned with error "no waitpid" ( i not found place this > error). > 5) destroy error in new version check xgetcwd()==NULL and set "(unknow)" - > this have error: crashe in next call `pwd`, but xgetcwd(not null) called > free(arg). > 6) next add integraion with libbb Valdimir's patch missed two cases of local variable handling FOO=bar export FOO=baz unset FOO and export FOO=bar FOO=baz which were working before, so I fixed those two cases. --- shell/hush.c | 382 ++++++++++++++++++++++++++++------------------------------- 1 file changed, 184 insertions(+), 198 deletions(-) (limited to 'shell') diff --git a/shell/hush.c b/shell/hush.c index 59568189f..a1e65b24e 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -227,6 +227,14 @@ struct close_me { struct close_me *next; }; +struct variables { + char *name; + char *value; + int flg_export; + int flg_read_only; + struct variables *next; +}; + /* globals, connect us to the outside world * the first three support $?, $#, and $1 */ char **global_argv; @@ -248,13 +256,14 @@ static const char *cwd; static struct jobset *job_list; static unsigned int last_bg_pid; static char *PS1; -static char *PS2; -static char **__shell_local_env; +static char PS2[] = "> "; + +struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 }; + +struct variables *top_vars = &shell_ver; #define B_CHUNK (100) #define B_NOSPAC 1 -#define MAX_LINE 256 /* for cwd */ -#define MAX_READ 256 /* for builtin_read */ typedef struct { char *data; @@ -303,12 +312,12 @@ static void debug_printf(const char *format, ...) va_end(args); } #else -static void debug_printf(const char *format, ...) { } +static inline void debug_printf(const char *format, ...) { } #endif #define final_printf debug_printf -void __syntax(char *file, int line) { - fprintf(stderr,"syntax error %s:%d\n",file,line); +static void __syntax(char *file, int line) { + error_msg("syntax error %s:%d", file, line); } #define syntax() __syntax(__FILE__, __LINE__) @@ -362,7 +371,6 @@ static int globhack(const char *src, int flags, glob_t *pglob); static int glob_needed(const char *s); static int xglob(o_string *dest, int flags, glob_t *pglob); /* variable assignment: */ -static int set_local_var(const char *s); static int is_assignment(const char *s); /* data structure manipulation: */ static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input); @@ -390,8 +398,8 @@ static void remove_bg_job(struct pipe *pi); static void free_pipe(struct pipe *pi); /* local variable support */ static char *get_local_var(const char *var); -static int set_local_var(const char *s); static void unset_local_var(const char *name); +static int set_local_var(const char *s, int flg_export); /* Table of built-in functions. They can be forked or not, depending on @@ -427,6 +435,17 @@ static struct built_in_command bltins[] = { {NULL, NULL, NULL} }; +static const char *set_cwd(void) +{ + if(cwd==unknown) + cwd = NULL; /* xgetcwd(arg) called free(arg) */ + cwd = xgetcwd((char *)cwd); + if (!cwd) + cwd = unknown; + return cwd; +} + + /* built-in 'cd ' handler */ static int builtin_cd(struct child_prog *child) { @@ -439,9 +458,7 @@ static int builtin_cd(struct child_prog *child) printf("cd: %s: %s\n", newdir, strerror(errno)); return EXIT_FAILURE; } - cwd = xgetcwd((char *)cwd); - if (!cwd) - cwd = unknown; + set_cwd(); return EXIT_SUCCESS; } @@ -477,43 +494,48 @@ static int builtin_exit(struct child_prog *child) /* built-in 'export VAR=value' handler */ static int builtin_export(struct child_prog *child) { - int res; - char *value, *name = child->argv[1]; + int res = 0; + char *name = child->argv[1]; if (name == NULL) { return (builtin_env(child)); } - value = strchr(name, '='); + name = strdup(name); + + if(name) { + char *value = strchr(name, '='); + if (!value) { - /* They are exporting something without an =VALUE. - * Assume this is a local shell variable they are exporting */ - name = get_local_var(name); - if (! name ) { - error_msg("export failed"); - return (EXIT_FAILURE); + char *tmp; + /* They are exporting something without an =VALUE */ + + value = get_local_var(name); + if (value) { + size_t ln = strlen(name); + + tmp = realloc(name, ln+strlen(value)+2); + if(tmp==NULL) + res = -1; + else { + sprintf(tmp+ln, "=%s", value); + name = tmp; + } + } else { + /* bash not put error and set error code + if exporting not defined variable */ + res = 1; } - /* FIXME -- I leak memory!!!!! */ - value = malloc(strlen(child->argv[1]) + strlen(name) + 2); - sprintf(value, "%s=%s", child->argv[1], name); - } else { - /* Bourne shells always put exported variables into the - * local shell variable list. Do that first... */ - set_local_var(name); - /* FIXME -- I leak memory!!!!! */ - value = strdup(name); - } - - /* FIXME -- I leak memory!!!!! - * It seems most putenv implementations place the very char* pointer - * we pass in directly into the environ array, so the memory holding - * this string has to be persistant. We can't even use the memory for - * the local shell variable list, since where that memory is keeps - * changing due to reallocs... */ - res = putenv(value); - if (res) + } + } + if (res<0) perror_msg("export"); - return (res); + else if(res==0) + res = set_local_var(name, 1); + else + res = 0; + free(name); + return res; } /* built-in 'fg' and 'bg' handler */ @@ -605,66 +627,52 @@ static int builtin_jobs(struct child_prog *child) /* built-in 'pwd' handler */ static int builtin_pwd(struct child_prog *dummy) { - cwd = xgetcwd((char *)cwd); - if (!cwd) - cwd = unknown; - puts(cwd); + puts(set_cwd()); return EXIT_SUCCESS; } /* built-in 'read VAR' handler */ static int builtin_read(struct child_prog *child) { - int res = 0, len, newlen; - char *s; - char string[MAX_READ]; + int res; if (child->argv[1]) { - /* argument (VAR) given: put "VAR=" into buffer */ - strcpy(string, child->argv[1]); - len = strlen(string); - string[len++] = '='; - string[len] = '\0'; - /* XXX would it be better to go through in_str? */ - fgets(&string[len], sizeof(string) - len, stdin); /* read string */ - newlen = strlen(string); - if(newlen > len) - string[--newlen] = '\0'; /* chomp trailing newline */ - /* - ** string should now contain "VAR=" - ** copy it (putenv() won't do that, so we must make sure - ** the string resides in a static buffer!) - */ + char string[BUFSIZ]; + char *var = 0; + + string[0] = 0; /* for correct work if stdin have "only EOF" */ + /* read string */ + fgets(string, sizeof(string), stdin); + chomp(string); + var = malloc(strlen(child->argv[1])+strlen(string)+2); + if(var) { + sprintf(var, "%s=%s", child->argv[1], string); + res = set_local_var(var, 0); + } else res = -1; - if((s = strdup(string))) - res = putenv(s); if (res) - fprintf(stderr, "read: %s\n", strerror(errno)); + fprintf(stderr, "read: %m\n"); + free(var); /* not move up - saved errno */ + return res; + } else { + do res=getchar(); while(res!='\n' && res!=EOF); + return 0; } - else - fgets(string, sizeof(string), stdin); - - return (res); } /* built-in 'set VAR=value' handler */ static int builtin_set(struct child_prog *child) { - int res; char *temp = child->argv[1]; + struct variables *e; + + if (temp == NULL) + for(e = top_vars; e; e=e->next) + printf("%s=%s\n", e->name, e->value); + else + set_local_var(temp, 0); - if (child->argv[1] == NULL) { - char **e = __shell_local_env; - if (e == NULL) return EXIT_FAILURE; - for (; *e; e++) { - puts(*e); - } return EXIT_SUCCESS; - } - res = set_local_var(temp); - if (res) - fprintf(stderr, "set: %s\n", strerror(errno)); - return (res); } @@ -697,7 +705,7 @@ static int builtin_source(struct child_prog *child) /* XXX search through $PATH is missing */ input = fopen(child->argv[1], "r"); if (!input) { - fprintf(stderr, "Couldn't open file '%s'\n", child->argv[1]); + error_msg("Couldn't open file '%s'", child->argv[1]); return EXIT_FAILURE; } @@ -732,11 +740,7 @@ static int builtin_umask(struct child_prog *child) /* built-in 'unset VAR' handler */ static int builtin_unset(struct child_prog *child) { - if (child->argv[1] == NULL) { - fprintf(stderr, "unset: parameter required.\n"); - return EXIT_FAILURE; - } - unsetenv(child->argv[1]); + /* bash returned already true */ unset_local_var(child->argv[1]); return EXIT_SUCCESS; } @@ -998,8 +1002,7 @@ static int setup_redirects(struct child_prog *prog, int squirrel[]) if (openfd < 0) { /* this could get lost if stderr has been redirected, but bash and ash both lose it as well (though zsh doesn't!) */ - fprintf(stderr,"error opening %s: %s\n", redir->word.gl_pathv[0], - strerror(errno)); + perror_msg("error opening %s", redir->word.gl_pathv[0]); return 1; } } else { @@ -1160,10 +1163,9 @@ static void insert_bg_job(struct pipe *pi) /* physically copy the struct job */ memcpy(thejob, pi, sizeof(struct pipe)); thejob->next = NULL; - //thejob->num_progs = 0; thejob->running_progs = thejob->num_progs; thejob->stopped_progs = 0; - thejob->text = xmalloc(MAX_LINE); + thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */ //if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) { @@ -1327,7 +1329,7 @@ static int run_pipe_real(struct pipe *pi) if (i!=0 && child->argv[i]==NULL) { /* assignments, but no command: set the local environment */ for (i=0; child->argv[i]!=NULL; i++) { - set_local_var(child->argv[i]); + set_local_var(child->argv[i], 0); } return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */ } @@ -1646,12 +1648,10 @@ static int xglob(o_string *dest, int flags, glob_t *pglob) gr = globhack(dest->data, flags, pglob); debug_printf("globhack returned %d\n",gr); } - if (gr == GLOB_NOSPACE) { - fprintf(stderr,"out of memory during glob\n"); - exit(1); - } + if (gr == GLOB_NOSPACE) + error_msg_and_die("out of memory during glob"); if (gr != 0) { /* GLOB_ABORTED ? */ - fprintf(stderr,"glob(3) error %d\n",gr); + error_msg("glob(3) error %d",gr); } /* globprint(glob_target); */ return gr; @@ -1660,129 +1660,113 @@ static int xglob(o_string *dest, int flags, glob_t *pglob) /* This is used to get/check local shell variables */ static char *get_local_var(const char *s) { - char **p; - int len; + struct variables *cur; if (!s) return NULL; - if (!__shell_local_env) - return NULL; - len = strlen(s); - - for (p = __shell_local_env; *p; p++) { - if (memcmp(s, *p, len) == 0 && (*p)[len] == '=') { - return *p + len + 1; - } - } + for (cur = top_vars; cur; cur=cur->next) + if(strcmp(cur->name, s)==0) + return cur->value; return NULL; } -/* This is used to set local shell variables */ -static int set_local_var(const char *s) +/* This is used to set local shell variables + flg_export==0 if only local (not exporting) variable + flg_export==1 if "new" exporting environ + flg_export>1 if current startup environ (not call putenv()) */ +static int set_local_var(const char *s, int flg_export) { - char **ep; - char *tmp,*name, *value; - size_t size; - size_t namelen; - size_t vallen; + char *name, *value; int result=0; + struct variables *cur; + char *newval = 0; - name=tmp=strdup(s); + name=strdup(s); /* Assume when we enter this function that we are already in * NAME=VALUE format. So the first order of business is to * split 's' on the '=' into 'name' and 'value' */ value = strchr(name, '='); - if (!value) { + if (value==0 || (newval = strdup(value+1))==0) { result = -1; - goto done_already; - } - *value='\0'; - ++value; - - namelen = strlen (name); - vallen = strlen (value); + } else { + *value++ = 0; - /* Now see how many local environment entries we have, and check - * if we match an existing environment entry (so we can overwrite it) */ - size = 0; - for (ep = __shell_local_env; ep && *ep != NULL; ++ep) { - if (!memcmp (*ep, name, namelen) && (*ep)[namelen] == '=') + for(cur = top_vars; cur; cur = cur->next) + if(strcmp(cur->name, name)==0) break; - else - ++size; - } - if (ep == NULL || *ep == NULL) { - static char **last_environ = NULL; - char **new_environ = (char **) malloc((size + 2) * sizeof(char *)); - if (new_environ == NULL) { - result = -1; - goto done_already; - } - memcpy((__ptr_t) new_environ, (__ptr_t) __shell_local_env, - size * sizeof(char *)); - - new_environ[size] = malloc (namelen + 1 + vallen + 1); - if (new_environ[size] == NULL) { - free (new_environ); - errno=ENOMEM; + if(cur) { + if(strcmp(cur->value, value)==0) { + result = cur->flg_export == flg_export; + } else { + if(cur->flg_read_only) { result = -1; - goto done_already; + error_msg("%s: readonly variable", name); + } else { + free(cur->value); + cur->value = newval; + newval = 0; /* protect free */ } - memcpy (new_environ[size], name, namelen); - new_environ[size][namelen] = '='; - memcpy (&new_environ[size][namelen + 1], value, vallen + 1); - - new_environ[size + 1] = NULL; - - if (last_environ != NULL) - free ((__ptr_t) last_environ); - last_environ = new_environ; - __shell_local_env = new_environ; - } - else { - size_t len = strlen (*ep); - if (len < namelen + 1 + vallen) { - char *new = malloc (namelen + 1 + vallen + 1); - if (new == NULL) { + } + } else { + cur = malloc(sizeof(struct variables)); + if(cur==0) { result = -1; - goto done_already; + } else { + cur->name = strdup(name); + if(cur->name == 0) { + free(cur); + result = -1; + } else { + struct variables *bottom = top_vars; + + cur->value = newval; + newval = 0; /* protect free */ + cur->next = 0; + cur->flg_export = flg_export; + cur->flg_read_only = 0; + while(bottom->next) bottom=bottom->next; + bottom->next = cur; } - *ep = new; - memcpy (*ep, name, namelen); - (*ep)[namelen] = '='; } - memcpy (&(*ep)[namelen + 1], value, vallen + 1); } - - /* One last little detail... If this variable is already - * in the environment we must set it there as well... */ - tmp = getenv(name); - if (tmp) { - /* FIXME -- I leak memory!!!!! */ - putenv(strdup(s)); } -done_already: + if((result==0 && flg_export==1) || (result>0 && cur->flg_export>0)) { + *(value-1) = '='; + result = putenv(name); + } else { free(name); + if(result>0) /* equivalent to previous set */ + result = 0; + } + free(newval); return result; } static void unset_local_var(const char *name) { - char **ep, **dp; - size_t namelen; + struct variables *cur; - if (!name) + if (name) { + for (cur = top_vars; cur; cur=cur->next) + if(strcmp(cur->name, name)==0) + break; + if(cur!=0) { + struct variables *next = top_vars; + if(cur==next) return; - namelen = strlen(name); - for (dp = ep = __shell_local_env; ep && *ep != NULL; ++ep) { - if (memcmp (*ep, name, namelen)==0 && (*ep)[namelen] == '=') { - *dp = *ep; - ++dp; - *ep = NULL; - break; + else { + if(cur->flg_export) + unsetenv(cur->name); + free(cur->name); + free(cur->value); + while (next->next != cur) + next = next->next; + next->next = cur->next; + } + free(cur); } } } @@ -1963,7 +1947,7 @@ static int done_word(o_string *dest, struct p_context *ctx) if (ctx->pending_redirect) { ctx->pending_redirect=NULL; if (glob_target->gl_pathc != 1) { - fprintf(stderr, "ambiguous redirect\n"); + error_msg("ambiguous redirect"); return 1; } } else { @@ -2049,7 +2033,7 @@ static int redirect_dup_num(struct in_str *input) } if (ok) return d; - fprintf(stderr, "ambiguous redirect\n"); + error_msg("ambiguous redirect"); return -2; } @@ -2261,7 +2245,7 @@ static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *i case '-': case '_': /* still unhandled, but should be eventually */ - fprintf(stderr,"unhandled syntax: $%c\n",ch); + error_msg("unhandled syntax: $%c",ch); return 1; break; default: @@ -2505,16 +2489,14 @@ int shell_main(int argc, char **argv) int opt; FILE *input; struct jobset joblist_end = { NULL, NULL }; + char **e = environ; - /* (re?) initialize globals */ - ifs=NULL; - fake_mode=0; - interactive=0; - close_me_head = NULL; + /* initialize globals */ + if (e) { + for (; *e; e++) + set_local_var(*e, 2); /* without call putenv() */ + } job_list = &joblist_end; - last_bg_pid=0; - PS2 = "> "; - __shell_local_env = 0; last_return_code=EXIT_SUCCESS; @@ -2581,9 +2563,13 @@ int shell_main(int argc, char **argv) fake_mode++; break; default: +#ifndef BB_VER fprintf(stderr, "Usage: sh [FILE]...\n" " or: sh -c command [args]...\n\n"); exit(EXIT_FAILURE); +#else + show_usage(); +#endif } } /* A shell is interactive if the `-i' flag was given, or if all of -- cgit v1.2.3