X-Git-Url: https://diplodocus.org/git/nmh/blobdiff_plain/dffeac1b8759bbedb385d0d2003a6d4c6c008cd5..791576c7f643c97ca087720751ea89f357c5b8fa:/sbr/utils.c?ds=sidebyside

diff --git a/sbr/utils.c b/sbr/utils.c
index cf920a39..7731c9b3 100644
--- a/sbr/utils.c
+++ b/sbr/utils.c
@@ -25,62 +25,73 @@ extern char *mhdocdir;
  */
 #define MAXMSGS 256
 
-/*
- * Safely call malloc
- */
-void *
-mh_xmalloc(size_t size)
+/* Call malloc(3), exiting on NULL return. */
+void *mh_xmalloc(size_t size)
 {
-    void *memory;
+    void *p;
 
     if (size == 0)
-        adios(NULL, "Tried to malloc 0 bytes");
-
-    memory = malloc(size);
-    if (!memory)
-        adios(NULL, "Malloc failed");
+        size = 1; /* Some mallocs don't like 0. */
+    p = malloc(size);
+    if (!p)
+        adios(NULL, "malloc failed, size wanted: %zu", size);
 
-    return memory;
+    return p;
 }
 
-/*
- * Safely call realloc
- */
-void *
-mh_xrealloc(void *ptr, size_t size)
+/* Call realloc(3), exiting on NULL return. */
+void *mh_xrealloc(void *ptr, size_t size)
 {
-    void *memory;
+    void *new;
 
-    /* Some non-POSIX realloc()s don't cope with realloc(NULL,sz) */
+    /* Copy POSIX behaviour, coping with non-POSIX systems. */
+    if (size == 0) {
+        mh_xfree(ptr);
+        return mh_xmalloc(1); /* Get a unique pointer. */
+    }
     if (!ptr)
         return mh_xmalloc(size);
 
-    if (size == 0)
-        adios(NULL, "Tried to realloc 0bytes");
+    new = realloc(ptr, size);
+    if (!new)
+        adios(NULL, "realloc failed, size wanted: %zu", size);
+
+    return new;
+}
+
+/* Call calloc(3), exiting on NULL return. */
+void *mh_xcalloc(size_t nelem, size_t elsize)
+{
+    void *p;
+
+    if (!nelem || !elsize)
+        return mh_xmalloc(1); /* Get a unique pointer. */
 
-    memory = realloc(ptr, size);
-    if (!memory)
-        adios(NULL, "Realloc failed");
+    p = calloc(nelem, elsize);
+    if (!p)
+        adios(NULL, "calloc failed, size wanted: %zu * %zu", nelem, elsize);
 
-    return memory;
+    return p;
 }
 
-/*
- * Safely call calloc
- */
-void *
-mh_xcalloc(size_t nmemb, size_t size)
+/* Duplicate a NUL-terminated string, exit on failure. */
+char *mh_xstrdup(const char *src)
 {
-    void *memory;
+    size_t n;
+    char *dest;
 
-    if (nmemb == 0  ||  size == 0)
-        adios(NULL, "Tried to calloc 0 bytes");
+    n = strlen(src) + 1; /* Ignore possibility of overflow. */
+    dest = mh_xmalloc(n);
+    memcpy(dest, src, n);
 
-    if ((memory = calloc(nmemb, size))) {
-        return memory;
-    } else {
-        adios(NULL, "calloc failed");
-    }
+    return dest;
+}
+
+/* Call free(3), if ptr isn't NULL. */
+void mh_xfree(void *ptr)
+{
+    if (ptr)
+        free(ptr); /* Some very old platforms can't cope with NULL. */
 }
 
 /*
@@ -90,11 +101,11 @@ mh_xcalloc(size_t nmemb, size_t size)
 char *
 pwd(void)
 {
-    register char *cp;
+    char *cp;
     static char curwd[PATH_MAX];
 
     if (!getcwd (curwd, PATH_MAX)) {
-        admonish (NULL, "unable to determine working directory");
+        inform("unable to determine working directory, continuing...");
         if (!mypath || !*mypath
                 || (strcpy (curwd, mypath), chdir (curwd)) == -1) {
             strcpy (curwd, "/");
@@ -168,22 +179,10 @@ addlist (char *list, const char *item)
 int folder_exists(const char *folder)
 {
     struct stat st;
-    int exists = 0;
-
-    if (stat (folder, &st) == -1) {
-        /* The folder either doesn't exist, or we hit an error.  Either way
-         * return a failure.
-         */
-        exists = 0;
-    } else {
-        /* We can see a folder with the right name */
-        exists = 1;
-    }
 
-    return exists;
+    return stat(folder, &st) != -1;
 }
 
-
 /*
  * create_folder
  *      Check to see if a folder exists, if not, prompt the user to create
@@ -347,12 +346,100 @@ nmh_strcasestr (const char *s1, const char *s2) {
 }
 
 
+/* truncpy copies at most size - 1 chars from non-NULL src to non-NULL,
+ * non-overlapping, dst, and ensures dst is NUL terminated.  If size is
+ * zero then it aborts as dst cannot be NUL terminated.
+ *
+ * It's to be used when truncation is intended and correct, e.g.
+ * reporting a possibly very long external string back to the user.  One
+ * of its advantages over strncpy(3) is it doesn't pad in the common
+ * case of no truncation. */
+void trunccpy(char *dst, const char *src, size_t size)
+{
+    if (!size) {
+        inform("trunccpy: zero-length destination: \"%.20s\"",
+            src ? src : "null");
+        abort();
+    }
+
+    if (strnlen(src, size) < size) {
+        strcpy(dst, src);
+    } else {
+        memcpy(dst, src, size - 1);
+        dst[size - 1] = '\0';
+    }
+}
+
+
+/* has_prefix returns true if non-NULL s starts with non-NULL prefix. */
+bool has_prefix(const char *s, const char *prefix)
+{
+    while (*s && *s == *prefix) {
+        s++;
+        prefix++;
+    }
+
+    return *prefix == '\0';
+}
+
+
+/* has_suffix returns true if non-NULL s ends with non-NULL suffix. */
+bool has_suffix(const char *s, const char *suffix)
+{
+    size_t ls, lsuf;
+
+    ls = strlen(s);
+    lsuf = strlen(suffix);
+
+    return lsuf <= ls && !strcmp(s + ls - lsuf, suffix);
+}
+
+
+/* has_suffix_c returns true if non-NULL string s ends with a c before the
+ * terminating NUL. */
+bool has_suffix_c(const char *s, int c)
+{
+    return *s && s[strlen(s) - 1] == c;
+}
+
+
+/* trim_suffix_c deletes c from the end of non-NULL string s if it's
+ * present, shortening s by 1.  Only one instance of c is removed. */
+void trim_suffix_c(char *s, int c)
+{
+    if (!*s)
+        return;
+
+    s += strlen(s) - 1;
+    if (*s == c)
+        *s = '\0';
+}
+
+
+/* to_lower runs all of s through tolower(3). */
+void to_lower(char *s)
+{
+    unsigned char *b;
+
+    for (b = (unsigned char *)s; (*b = tolower(*b)); b++)
+        ;
+}
+
+
+/* to_upper runs all of s through toupper(3). */
+void to_upper(char *s)
+{
+    unsigned char *b;
+
+    for (b = (unsigned char *)s; (*b = toupper(*b)); b++)
+        ;
+}
+
+
 int
 nmh_init(const char *argv0, int read_context) {
-    if (! setlocale(LC_ALL, "")) {
-        admonish(NULL, "setlocale failed, check your LC_ALL, LC_CTYPE, and "
-                 "LANG environment variables");
-    }
+    int status = OK;
+    char *locale;
 
     invo_name = r1bindex ((char *) argv0, '/');
 
@@ -390,30 +477,39 @@ nmh_init(const char *argv0, int read_context) {
             isatty (fileno (stdout))  &&  isatty (fileno (stderr))) {
             if (nmh_version_changed (check_older_version)) {
                 printf ("==================================================="
-                        "====================\n");
+                        "=====================\n");
                 printf ("Welcome to nmh version %s\n\n", VERSION);
-                printf ("See the release notes in %s/NEWS .\n\n",
+                printf ("See the release notes in %s/NEWS\n\n",
                          mhdocdir);
                 print_intro (stdout, 1);
                 printf ("\nThis message will not be repeated until "
                         "nmh is next updated.\n");
                 printf ("==================================================="
-                        "====================\n\n");
+                        "=====================\n\n");
 
                 fputs ("Press enter to continue: ", stdout);
                 (void) read_line ();
                 putchar ('\n');
             }
         }
-
-        return OK;
     } else {
-        int status = context_foil(NULL);
-        if (status != OK) {
-            advise("", "failed to create minimal profile/conext");
+        if ((status = context_foil(NULL)) != OK) {
+            advise("", "failed to create minimal profile/context");
         }
-        return status;
     }
+
+    /* Allow the user to set a locale in their profile.  Otherwise, use the
+       "" string to pull it from their environment, see setlocale(3). */
+    if ((locale = context_find ("locale")) == NULL) {
+        locale = "";
+    }
+
+    if (! setlocale (LC_ALL, locale)) {
+        inform("setlocale failed, check your LC_ALL, LC_CTYPE, and LANG "
+	    "environment variables, continuing...");
+    }
+
+    return status;
 }
 
 
@@ -431,7 +527,7 @@ nmh_version_changed (int older) {
            break for versions with multiple decimal points, etc. */
         const float current_version = strtof (VERSION, NULL);
         const float old_version =
-            context_version  &&  strncmp (context_version, "nmh-", 4) == 0
+            context_version  &&  has_prefix(context_version, "nmh-")
             ?  strtof (context_version + 4, NULL)
             :  99999999;
 
@@ -440,15 +536,14 @@ nmh_version_changed (int older) {
         }
 
         return old_version < current_version  ?  1  :  0;
-    } else {
-        if (context_version == NULL  ||  strcmp(context_version, "nmh-" VERSION) != 0) {
-            context_replace ("Version", "nmh-" VERSION);
+    }
 
-            return 1;
-        } else {
-            return 0;
-        }
+    if (context_version == NULL  ||  strcmp(context_version, "nmh-" VERSION) != 0) {
+        context_replace ("Version", "nmh-" VERSION);
+        return 1;
     }
+
+    return 0;
 }
 
 
@@ -457,9 +552,8 @@ nmh_version_changed (int older) {
 char *
 upcase (const char *str) {
     char *up = cpytrim (str);
-    char *cp;
 
-    for (cp = up; *cp; ++cp) { *cp = toupper ((unsigned char) *cp); }
+    to_upper(up);
 
     return up;
 }
@@ -484,3 +578,25 @@ contains8bit(const char *start, const char *end)
 
     return 0;
 }
+
+
+/*
+ * See if input has any 8-bit bytes.
+ */
+int
+scan_input (int fd, int *eightbit) {
+    int state;
+    char buf[BUFSIZ];
+
+    *eightbit = 0;
+    lseek (fd, (off_t) 0, SEEK_SET);
+
+    while ((state = read (fd, buf, sizeof buf)) > 0) {
+        if (contains8bit (buf, buf + state)) {
+            *eightbit = 1;
+            return OK;
+        }
+    }
+
+    return state == NOTOK  ?  NOTOK  :  OK;
+}